KEEPERS: 2019 Building Blocks—3B

Photo: Vladimir Guerrero, Jr. (3B, TOR)

This is our annual off-season series focused on helping keeper league and dynasty owners identify emerging targets that can ensure perennial title contention. We've refreshed the format this year and have renamed the series "Building Blocks," but the goal remains the same: To identify top prospects and young players at each position who can be procured before they become household names, so keeper league owners can continually build upon the foundation for long-term success that prevents the need for white-flag-waving, tanking-oriented rebuilds.

Each week we will examine a different position, looking for players (“pieces”) that have potential to be solid long-term contributors to a winning fantasy franchise. Obviously different keeper/dynasty formats allow for varying degrees of speculation on unproven players, so you will need to adjust your sights on these targets, accordingly. For the purpose of this series, we group players under four general designations:

Cornerstones: Premium quality franchise difference-makers, essential to the foundation of a true dynasty juggernaut. These pieces are top priority acquisitions, either by draft or trade.

Building Blocks: High quality prospects with potential to be solid elements of a winning core. Desirable pieces that should be targeted as part of the ongoing championship franchise building process.

Support Pieces: Interchangeable lower grade parts that may provide help in a specific category or offer a lower ceiling than more desirable foundation pieces.

Dicey Accessories: Lower probability, high-risk players who may be targeted for upside gambles, but who should not be counted on as core championship pieces. (Possible trade-chip candidates if timed properly.)

Players are listed with 2019 season age and major league organization, along with a designation if left-handed hitter (*) or switch-hitter (#). Please see the Organization Reports in our Scouting section for more detailed analysis on specific players and be sure to pick up a copy of the Minor League Baseball Analyst which makes a great complement to the indispensable Baseball Forecaster for league-winning insights on all relevant players.

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We will attempt to identify top building targets within the following criteria:

  • ​Will play majority of 2019 season at 25 years old or younger (25 as of July 1, 2019)
  • Less than 200 MLB AB in 2018 and less than 500 MLB AB career
  • Reasonably projected to be MLB-ready prior to conclusion of 2020 season (may extend time horizon for Cornerstones)

Previous articles in this series:  C  |  1B  |  2B

In this edition we continue our tour around the diamond at third base. The much anticipated arrival of Vladimir Guerrero, Jr. has rightfully dominated prospect talk, but there are other prospects with excellent keeper potential who can be considered this year, as well.


Vladimir Guerrero, Jr. (20 years old, TOR) – What else can be said about Vlad Junior that you haven’t already read somewhere else? How about this—if he’s not yet rostered in your keeper league, you need to resign your team immediately and switch to a more competitive league. A plus-plus-PLUS hit tool combined with plus-plus-plus power simply doesn’t come along too often. Of course there is risk—nothing is guaranteed, but if you are the owner of young Guerrero, you’re feeling pretty good about yourself, and if you don’t have him, good luck trying to pry him out of some other owner’s tight clench. About the biggest question remaining at this point is what level of absurdity with the Blue Jays sink to in explaining why Vlad is not fit to break camp with the big club and needs precisely 20 more days of minor league “development.”

Nolan Jones* (21, CLE) – An outstanding all-fields approach with plus power and tremendous plate discipline makes Jones the type of investment cherished by perennial championship contenders. Considered one of the top prep hitters in the 2016 draft, the sweet-swinging lefty has not missed a beat since signing. He finished the 2018 season by holding his own at high-A and could very easily be ready to make an impact at the big league level by 2020. While he will not be a factor in the stolen base category, the rest of the package is extremely attractive.



Nick Senzel (24, CIN) – An excellent hitter who consistently drives the ball to all fields, the biggest hurdle Senzel has faced is staying on the field. The biggest concern has been a mysterious vertigo malady that prematurely ended his 2017 season and popped up again in May of 2018, causing him to miss four weeks. Unexplained vertigo is the same ailment that forced a sudden end to the career of slugger Nick Esasky just over a quarter century ago. On the positive side of things, Senzel was looking as good as ever when he returned from his second bout of vertigo, mashing .380/.432/.608 over a 19-game stretch when a fractured finger on June 22 forced another premature end to his campaign. Surgery to remove bone spurs from his left (non-throwing) elbow in October capped off an injury riddled year. At least his versatility appears to be on the rise. A third baseman by trade, Senzel appeared most often at second base during the 2018 season (and this is the position at which he'll appear at for MLBA and BaseballHQ prospect purposes), followed by working out in the outfield during instructional league early in the fall. This will not only increase his potential fantasy utility, but should improve his odds of making a big league impact early in 2019. While Senzel’s talents are Cornerstone caliber, the fact that he has now twice had to deal with vertigo that came on without warning presents a level of risk that cannot be ignored by the dynasty league investor.

Ke’Bryan Hayes (22, PIT) – While his superb glovework at the hot corner is arguably his top real-life baseball attribute, his offensive upside may be underappreciated in the fantasy world. With an excellent all-fields approach at the plate complimented by useful speed, the only thing missing from Hayes game over his first three years as a pro was power. That changed in 2018, as he slugged a career-best .444 while knocking 31 doubles and seven home runs at pitcher-friendly double-A Altoona. With power now starting to show, the slick-fielding Hayes now profiles as a rare potential five-category contributor at the hot corner.

Colton Welker (21, COL) – A fine hitter with a good all-fields approach, Welker’s attractiveness is enhanced by the prospect of playing half his games in Coors Field. The enthusiasm is tempered a bit by the fact that he currently plays the same position as Rockies all-star Nolan Arenado. Welker, who played shortstop in high school, could possibly shift to corner outfield or to first base where he played a handful of games last year if necessary.

Austin Riley, (22, ATL) – A power bat with a rocket arm, Riley projects as a prototypical third baseman. A poor 67-percent contact rate in his first exposure to triple-A pitching, combined with the Braves signing slugging third baseman Josh Donaldson to a one-year contract both figure to delay Riley’s big league promotion for at least the first part of 2019. The organization, however, has made noise about him receiving work in the outfield in spring training. He also needs to force his way onto the 40-man roster.



Michael Chavis (23, BOS) – The luster of a breakout 2017 quickly dimmed when Chavis was handed an 80-game suspension for PEDs the following April. An abbreviated 46-game season following the suspension spent mostly at double-A saw him post a fine .298/.381/.538 line, so it appears to simply be a blip in his development provided there are no further issues. A relatively marginal 7.6% walk rate as a professional does raise some level of concern. Chavis reportedly received work at both second base and left field in instructional league in an effort to improve his versatility. How he performs as he is moved around in 2019 will go a long way toward determining his future as he is expected to spend the majority of 2019 at triple-A.



Bobby Dalbec (24, BOS) – Named both the offensive and defensive player of the year in their farm system by the Boston Red Sox following the 2018 season, big-time power is Dalbec’s calling card. He mashed 32 home runs between high-A and double-A while slugging a combined .558. Not surprisingly, strikeouts are an issue with this profile. The major question with Dalbec is just how big an issue they will be, as holds a miserable 62-percent contact rate over three professional seasons. Scouting reports have mentioned difficulty with both breaking ball recognition and catching up to good fastballs. That’s a deadly combination against advanced pitching. Concern was only heightened as Dalbec’s contact rate dipped to an alarming 59 percent following a late-season promotion to double-A and then plummeted down to 56 percent as he paced the Arizona Fall League with 32 strikeouts in 20 games. The power and the arm are legit, but the strikeout issues, particularly at the higher levels of competition in 2018, provide enough risk that caution is warranted.

Ryan Mountcastle (22, BAL) – A plus hit tool and plus power are effectively marginalized by a putrid 4.7-percent walk rate. His aggressive approach has limited Mountcastle to a .322 career OBP as a professional despite boasting a fine .287 average. Perhaps the biggest concern, however, is that questionable arm strength will mandate a move to first base or left field, placing further pressure on his bat to produce.



Yandy Diaz (27, TAM) – Dealt to Tampa Bay in December after posting a .312/.375/.422 line over 39 games with Cleveland, the Rays reportedly view Diaz as both an offensive and defensive upgrade over Jake Bauers, who was dealt away in the same deal. While he may not generate much power and won’t swipe more than the occasional base, Diaz appears to be in line for significant playing time at the corners and could be a useful source of other counting stats while providing a batting average boost.

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  For more information about the terms used in this article, see our Glossary Primer.