Each week in this report, I’ll be monitoring the performances of MLB rookies. I will emphasize those rookies who put up especially positive performances, while also taking care to mention rookies who are underperforming expectations. In both cases, I will dig into the underlying stats and attempt the difficult task of projecting forward.
Rookies are typically more unpredictable than their more experienced colleagues, and can, therefore, be a source of great profit in fantasy baseball, or great frustration. Stay tuned to this space every week to find out which newbies should be in the mix for your squad. Check out last week’s Rookie Report to keep up to date on all the hottest youngsters.
Stats are generally current prior to Tuesday’s games, and, as noted in week 3, any quoted Statcast numbers are directly from Baseball Savant.
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Matt Chapman (3B – OAK)
This preseason, I hyped another Oakland third baseman, Ryon Healy. So far, he has done nothing but deliver for fantasy owners, although his poor defense has moved him primarily to designated hitter. Into the void left by Trevor Plouffe, enter Matt Chapman, the 24-year-old Cal State Fullerton product who is universally graded as a plus defender at third, but whose raw power is undermined by contact issues. Chapman sat right around the top-100 prospects before his call-up according to both the consensus rankings and Bobby Sylvester’s own rankings. In four games prior to being sidelined with a knee inflection, Chapman showed his ability to take a walk (12.5% BB%) and propensity to strikeout (43.8% K%). With just a .598 OPS, he has not yet shown his above-average raw power, though his 95.8 mph average exit velocity on line drives and fly balls would be higher than air-ball revolutionary teammates Yonder Alonso and Ryon Healy should he maintain that velocity over more than his current seven batted balls. Assuming he recovers quickly from his knee infection, Chapman seems to have the A’s third base job locked down. Expect him to be a low average hitter with occasional bursts of power, more useful in OBP leagues than standard. His low minor league success rate does not portend many stolen bases. Overall, Chapman seems like a player to monitor for signs of plate discipline improvement entering 2018, but not one who should be counted on for much this season.
Brian Goodwin (OF – WAS)
Along with Michael Taylor, Goodwin was given a chance to play for the Nationals with Adam Eaton, Chris Heisey, and Jayson Werth on the DL. While his raw power and speed both earned above average scouting grades, questions about his contact and age relative to level have kept Goodwin well outside the top-200 prospects on both the consensus rankings and Sylvester’s. So far in the majors, Goodwin has controlled his strikeouts and chipped in a few walks. With four homers in his 31 games played, Goodwin has posted a .253 ISO despite not having exceeded .200 in any minor league season since 2012. His expected weighted on-base average (xwOBA) of .292 is significantly below his .333 mark so far, indicating that leaner times may be ahead. With just one steal, we have yet to see much indication of Goodwin’s speed potential, although seasons of 15 and 17 steals in the minors in 2015 and 2016 offer some hope for a handful of steals. With no recent news on Heisey’s stalled rehab and Werth yet to resume baseball activities, Goodwin will likely continue to serve on the strong side of an outfield platoon. Without full playing time, Goodwin’s iffy production is unlikely to be useful for mixed-leaguers.
Nick Pivetta (SP – PHI)
At age-24 repeating Triple-A to start the season, Pivetta absolutely dominated that level with a 1.41 ERA, 0.84 WHIP, and 10.41 K/9. In seven starts across two different major league stints, Pivetta has pitched to a 4.46 ERA and 1.60 WHIP entering Wednesday night’s start. In that start, however, he struck out 10, walked one, but allowed three earned runs in 6 innings. The 10 K outburst came after a 9 K, 2 BB outing against the Red Sox. Between his previous 2 K start and the Red Sox game, Pivetta seems to have cut way down on curveballs, throwing 3.3% and 5.6% curves, after 28% and 16% the previous two outings, adding more sliders and changeups. While his curve has yet to allow an extra-base hit, his slider generates more whiffs (16% vs. 9% for the curve). While relatively unheralded as a prospect, Pivetta seems to have developed some intriguing strikeout potential and if he can limit his walks, could be a sneaky flier in mixed leagues. While he wasn’t able to hold his own against the Diamondbacks in the desert, try giving him a stream in his next start against the Mets.
Francis Martes (SP/RP – HOU)
Checking in at 21 and 39 on the consensus and Sylvester’s prospect ranks, Martes carried some pedigree entering the season, having recorded nearly a strikeout per inning in the minors while being young for every level. He has averaged 95.0 mph on his fastball so far in the majors, which jives with his plus scouting profile grade, and his plus curveball has already generated 18.7% whiffs. All this talent, though, has failed to help him suppress runs at Triple-A or the majors so far. As with many pitchers, he also has a bit of an issue with free passes. More importantly, neither Dallas Keuchel nor Lance McCullers are expected to be out much longer, so Martes will likely find himself back in the minors soon. Martes could use a bit more seasoning, especially while the Astros are in win-now mode.
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Andrew Dominijanni is a correspondent at FantasyPros. For more from Andrew, check out his archive and follow him @ADominijanni.
