Forecaster's Toolbox: Prospects

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Minor league prospecting in perspective

In our perpetual quest to be the genius who uncovers the next Mike Trout when he’s still in high school, there is an obsessive fascination with minor league prospects. That’s not to say that prospecting is not important. The issue is perspective: 

1.    During the 10 year period of 1996 to 2005, only 8% of players selected in the first round of the Major League Baseball First Year Player Draft went on to become stars.

2.    Some prospects are going to hit the ground running (Carlos Correa) and some are going to immediately struggle (Daniel Norris), no matter what level of hype follows them.

3.    Some prospects are going to start fast (since the league is unfamiliar with them) and then fade (as the league figures them out). Others will start slow (since they are unfamiliar with the opposition) and then improve (as they adjust to the competition). So if you make your free agent and roster decisions based on small early samples sizes, you are just as likely to be an idiot as a genius. 

4.    How any individual player will perform relative to his talent is largely unknown because there is a psychological element that is vastly unexplored. Some make the transition to the majors seamlessly, some not, completely regardless of how talented they are. 

5.    Still, talent is the best predictor of future success, so major league equivalent base performance indicators still have a valuable role in the process. As do scouting reports, carefully filtered. 

6.    Follow the player’s path to the majors. Did he have to repeat certain levels? Was he allowed to stay at a level long enough to learn how to adjust to the level of competition? A player with only two great months at Double-A is a good bet to struggle if promoted directly to the majors because he was never fully tested at Double-A, let alone Triple-A.

7.    Younger players holding their own against older competition is a good thing. Older players reaching their physical peak, regardless of their current address, can be a good thing too. The Stephen Vogts and Justin Turners can have some very profitable years.

8.    Remember team context. A prospect with superior potential often will not unseat a steady but unspectacular incumbent, especially one with a large contract.

9.    Don’t try to anticipate how a team is going to manage their talent, both at the major and minor league level. You might think it’s time to promote J.P. Crawford and give him an everyday role. You are not running the Phillies.

10.    Those who play in shallow, one-year leagues should have little cause to be looking at the minors at all. The risk versus reward is so skewed against you, and there is so much talent available with a track record, that taking a chance on an unproven commodity makes little sense. 

11.    Decide where your priorities really are. If your goal is to win, prospect analysis is just a part of the process, not the entire process. 

Factors affecting minor league stats (Terry Linhart)

1.    Often, there is an exaggerated emphasis on short-term performance in an environment that is supposed to focus on the long-term. Two poor outings don’t mean a 21-year-old pitcher is washed up.

2.    Ballpark dimensions and altitude create hitters parks and pitchers parks, but a factor rarely mentioned is that many parks in the lower minors are inconsistent in their field quality. Minor league clubs have limited resources to maintain field conditions, and this can artificially depress defensive statistics while inflating stats like batting average.

3.    Some players’ skills are so superior to the competition at their level that you can’t get a true picture of what they’re going to do from their stats alone.

4.    Many pitchers are told to work on secondary pitches in unorthodox situations just to gain confidence in the pitch. The result is an artificially increased number of walks. 

5.    The #3, #4, and #5 pitchers in the lower minors are truly longshots to make the majors. They often possess only two pitches and are unable to disguise the off-speed offerings. Hitters can see inflated statistics in these leagues.

Minor league level versus age

When evaluating minor leaguers, look at the age of the prospect in relation to the median age of the league he is in:

Low level A     Between 19-20
Upper level A     Around 20
Double-A          21
Triple-A          22

These are the ideal ages for prospects at the particular level. If a prospect is younger than most and holds his own against older and more experienced players, elevate his status. If he is older than the median, reduce his status. 

Triple-A experience as a leading indicator

The probability that a minor leaguer will immediately succeed in the majors can vary depending upon the level of Triple-A experience he has amassed at the time of call-up. 

                    BATTERS         PITCHERS
                 < 1 Yr    Full    <1 Yr    Full
Performed well     57%     56%      16%     56%
Performed poorly   21%     38%      77%     33%
2nd half drop-off  21%      7%       6%     10%

The odds of a batter achieving immediate MLB success was slightly more than 50-50. More than 80% of all pitchers promoted with less than a full year at Triple-A struggled in their first year in the majors. Those pitchers with a year in Triple-A succeeded at a level equal to that of batters.

Major League Equivalency (MLE)  (Bill James)

A formula that converts a player’s minor or foreign league statistics into a comparable performance in the major leagues. These are not projections, but conversions of current performance. MLEs contain adjustments for the level of play in individual leagues and teams. They work best with Triple-A stats, not quite as well with Double-A stats, and hardly at all with the lower levels. Foreign conversions are still a work in process. James’ original formula only addressed batting. Our research has devised conversion formulas for pitchers, however, their best use comes when looking at BPIs, not traditional stats.

Adjusting to the competition

All players must “adjust to the competition” at every level of professional play. Players often get off to fast or slow starts. During their second tour at that level is when we get to see whether the slow starters have caught up or whether the league has figured out the fast starters. That second half “adjustment” period is a good baseline for projecting the subsequent season, in the majors or minors.

Premature major league call-ups often negate the ability for us to accurately evaluate a player due to the lack of this adjustment period. For instance, a hotshot Double-A player might open the season in Triple-A. After putting up solid numbers for a month, he gets a call to the bigs, and struggles. The fact is, we do not have enough evidence that the player has mastered the Triple-A level. We don’t know whether the rest of the league would have caught up to him during his second tour of the league. But now he’s labeled as an underperformer in the bigs when in fact he has never truly proven his skills at the lower levels. 

Bull Durham prospects

There is some potential talent in older players—age 26, 27 or higher—who, for many reasons (untimely injury, circumstance, bad luck, etc.), don’t reach the majors until they have already been downgraded from prospect to suspect. Equating potential with age is an economic reality for major league clubs, but not necessarily a skills reality.

Skills growth and decline is universal, whether it occurs at the major league level or in the minors. So a high-skills journeyman in Triple-A is just as likely to peak at age 27 as a major leaguer of the same age. The question becomes one of opportunity—will the parent club see fit to reap the benefits of that peak performance? 

Prospecting these players for your fantasy team is, admittedly, a high risk endeavor, though there are some criteria you can use. Look for a player who is/has:

•    Optimally, age 27-28 for overall peak skills, age 30-31 for power skills, or age 28-31 for pitchers.

•    At least two seasons of experience at Triple-A. Career Double-A players are generally not good picks.

•    Solid base skills levels.

•    Shallow organizational depth at their position.

•    Notable winter league or spring training performance.

Players who meet these conditions are not typically draftable players, but worthwhile reserve or FAAB picks. 


MLE PX as a leading indicator  (Bill Macey) 

Looking at minor league performance (as MLE) in one year and the corresponding MLB performance the  subsequent year:    

                Year 1 MLE            Year 2 MLB 
Observations       496                   496 
Median PX           95                    96 
Percent PX > 100   43%                   46% 

In addition, 53% of the players had a MLB PX in year 2 that exceeded their MLE PX in year 1. A slight bias towards improved performance in year 2 is consistent with general career trajectories. 

    Year 1      Year 2     Pct.       Pct. MLB
    MLE PX      MLB PX     Incr       PX > 100 
    <= 50         61      70.3%         5.4% 
    51-75         85      69.6%        29.4% 
    76-100        93      55.2%        39.9% 
    101-125      111      47.4%        62.0% 
    126-150      119      32.1%        66.1% 
    > 150        142      28.6%        76.2% 

Slicing the numbers by performance level, there is a good amount of regression to the mean. 

Players rarely suddenly develop power at the MLB level if they didn’t previously display that skill at the minor league level. However, the relatively large gap between the median MLE PX and MLB PX for these players, 125 to 110, confirms the notion that the best players continue to improve once they reach the major leagues. 

MLE contact rate as a leading indicator  (Bill Macey) 

There is a strong positive correlation (0.63) between a player’s MLE ct% in Year 1 and his actual ct% at the MLB level in Year 2.  

            Year 1     Year 2                       
MLE ct%     MLE ct%    MLB ct% 
< 70%        69%        68% 
70% - 74%    73%        72% 
75% - 79%    77%        75% 
80% - 84%    82%        77%
85% - 89%    87%        82% 
90% +        91%        86% 
TOTAL        84%        79% 

There is very little difference between the median MLE BA in Year 1 and the median MLB BA in Year 2:

           Year 1    Year 2 
MLE ct%    MLE BA    MLB BA 
< 70%       .230     .270 
70% - 74%   .257    . 248 
75% - 79%   .248     .255 
80% - 84%   .257     .255 
85% - 89%   .266     .270 
90% +       .282     .273 
TOTAL       .261     .262 

Excluding the <70% cohort (which was a tiny sample size), there is a positive relationship between MLE ct% and MLB BA.  



BPIs as a leading indicator for pitching success

The percentage of hurlers that were good investments in the year that they were called up varied by the level of their historical minor league BPIs prior to that year.

Pitchers who had:           Fared well    Fared poorly
Good indicators                79%           21%
Marginal or poor indicators    18%           82%

The data used here were MLE levels from the previous two years, not the season in which they were called up. The significance? Solid current performance is what merits a call-up, but this is not a good indicator of short-term MLB success, because a) the performance data set is too small, typically just a few month’s worth of statistics, and b) for those putting up good numbers at a new minor league level, there has typically not been enough time for the scouting reports to make their rounds.

Minor league BPV as a leading indicator  (Al Melchior)

There is a link between minor league skill and how a pitching prospect will fare in his first 5 starts upon call-up.


PQS Avg    < 50    50-99    100+
0.0-1.9     60%     28%      19%
2.0-2.9     32%     40%      29%
3.0-5.0      8%     33%      52%

Pitchers who demonstrate sub-par skills in the minors (sub-50 BPV) tend to fare poorly in their first big league starts. Three-fifths of these pitchers register a PQS average below 2.0, while only 8% average over 3.0.

Fewer than 1 out of 5 minor leaguers with a 100+ MLE BPV go on to post a sub-2.0 PQS average in their initial major league starts, but more than half average 3.0 or better. 

Late season performance of rookie starting pitchers (Ray Murphy)

Given that a rookie’s second tour of the league provides insight as to future success, do rookie pitchers typically run out of gas? We studied 2002-2005, identified 56 rookies who threw at least 75 IP and analyzed their PQS logs. The group:

All rookies    #    #GS/P    DOM%    DIS%    qERA
before 7/31    56    13.3    42%     21%     4.56
after 7/31     56     9.3    37%     29%     4.82 

There is some erosion, but a 0.26 run rise in qERA is hardly cause for panic. If we re-focus our study class, the qERA variance increased to 4.44-5.08 for those who made at least 16 starts before July 31. The variance also was larger (3.97-4.56) for those who had a PQS-3 average prior to July 31. The pitchers who intersected these two sub-groups:

PQS>3+GS>15    #    #GS/P    DOM%    DIS%    qERA
before 7/31    8    19.1     51%     12%     4.23
after 7/31     8     9.6     34%     30%     5.08

While the sample size is small, the degree of flameout by these guys (0.85 runs) is more significant. 

Japanese Baseball (Tom Mulhall)

Comparing MLB and Japanese Baseball

The Japanese major leagues are generally considered to be equivalent to Triple-A ball and the pitching is thought to be even better. However, statistics are difficult to convert due to differences in the way the game is played in Japan. 

1.    While strong on fundamentals, Japanese baseball’s guiding philosophy is risk avoidance. Mistakes are not tolerated. Runners rarely take extra bases, batters focus on making contact rather than driving the ball, and managers play for one run at a time. Bunts are more common. As a result, offenses score fewer runs per number of hits, and pitching stats tend to look better than the talent behind them.

2.    Stadiums in Japan usually have much shorter fences. This should mean more HRs, but given #1 above, it is the American players who make up the majority of Japan’s power elite. No power hitters have made an equivalent transition to the MLB. 

3.    There are more artificial turf fields, which increases the number of ground ball singles. Only a small number of stadiums have infield grass and a few still use all dirt infields.

4.    The quality of umpiring is questionable and even inept. Fewer errors are called, reflecting the cultural philosophy of low tolerance for mistakes and the desire to avoid publicly embarrassing a player. Moreover, umpires are routinely intimidated, even physically. 

5.    Teams have smaller pitching staffs and use a six-man rotation. Starters usually pitch once a week, typically on the same day since Monday is an off-day for the entire league. Many starters will also occasionally pitch in relief between starts. Moreover, managers push for complete games, no matter what the score or situation. Because of the style of offense, higher pitch counts are common. Despite superior conditioning, Japanese pitchers tend to burn out early due to overuse.  

6.    The ball is smaller and lighter, and the strike zone is closer to the batter. A new ball was introduced in 2011 with lower-elasticity rubber surrounding the cork, which limited offense and inflated pitching stats. A more hitter-friendly ball was used in 2013 and home runs increased. But continue to exercise some skepticism when analyzing pitching stats and look for possible signs of optimism in hitting stats other than the power categories.

7.    Tie games are allowed. If the score remains even after 12 innings, the game goes into the books as a tie.   

8.  There are 18 fewer games in the Japanese schedule.

Japanese players as fantasy farm selections

Many fantasy leagues have large reserve or farm teams with rules allowing them to draft foreign players before they sign with a MLB team. With increased coverage by fantasy experts, the internet, and exposure from the World Baseball Classic, anyone willing to do a modicum of research can compile an adequate list of good players.  

However, the key is not to just identify the best Japanese players—the key is to identify impact players who have the desire and opportunity to sign with a MLB team. With the success of Darvish and Tanaka, it is easy to overestimate the value of drafting these players. But since 1995, less than four dozen Japanese players have made a big league roster, and about half of them were middle relievers. Still, for owners who are allowed to carry a large reserve or farm team at reduced salaries, these players could be a real windfall, especially if your competitors do not do their homework. 

A list of Japanese League players who could jump to the majors appears in the Prospects section.

Other Diamonds

Age 26 Paradox

Age 26 is when a player begins to reach his peak skill, no matter what his address is. If circumstances have him celebrating that birthday in the majors, he is a breakout candidate. If circumstances have him celebrating that birthday in the minors, he is washed up.

A-Rod 10-Step Path to Stardom

Not all well-hyped prospects hit the ground running. More often they follow an alternative path:

1.    Prospect puts up phenomenal minor league numbers.

2.    The media machine gets oiled up.

3.    Prospect gets called up, but struggles, Year 1.

4.    Prospect gets demoted.

5.    Prospect tears it up in the minors, Year 2.

6.    Prospect gets called up, but struggles, Year 2.

7.    Prospect gets demoted.

8.    The media turns their backs. Fantasy leaguers reduce their expectations.

9.    Prospect tears it up in the minors, Year 3. The public shrugs its collective shoulders.

10.    Prospect is promoted in Year 3 and explodes. Some lucky fantasy leaguer lands a franchise player for under $5.

Some players that are currently stuck at one of the interim steps, and may or may not ever reach Step 10, include Jesus Montero, Jonathan Singleton and Dalton Pompey.  

Developmental Dogmata

1.    Defense is what gets a minor league prospect to the majors; offense is what keeps him there. (Deric McKamey)

2.    The reason why rapidly promoted minor leaguers often fail is that they are never given the opportunity to master the skill of “adjusting to the competition.”

3.    Rookies who are promoted in-season often perform better than those that make the club out of spring training. Inferior March competition can inflate the latter group’s  perceived talent level.

4.    Young players rarely lose their inherent skills. Pitchers may uncover weaknesses and the players may have difficulty adjusting. These are bumps along the growth curve, but they do not reflect a loss of skill.

5.    Late bloomers have smaller windows of opportunity and much less chance for forgiveness.

6.    The greatest risk in this game is to pay for performance that a player has never achieved.

7.     Some outwardly talented prospects simply have a ceiling that’s spelled “A-A-A.”

Rule 5 Reminder

Don’t ignore the Rule 5 draft lest you ignore the possibility of players like Jose Bautista, Josh Hamilton, Johan Santana, Joakim Soria, Dan Uggla, Shane Victorino and Jayson Werth. All were Rule 5 draftees.

Trout Inflation

The tendency for rookies to go for exorbitant draft prices following a year when there was a very good rookie crop.