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. As I have begun to exhaust all the new interesting rookies, I will be revisiting some of the more noteworthy performers over the course of the season.
All stats are typically 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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Updates
Robert Gsellman (SP – NYM)
Back in week 1, I suggested that Gsellman would be an interesting streamer. In the interest of full disclosure, I was personally pretty optimistic on Gsellman this pre-season. I saw some good fortune in his 2016 ERA, but believed in his heavy sinker and potential for above-average strikeout rate. So far in 2017, Gsellman has improved his groundball rate, but lost the swing-and-miss stuff, and failed to suppress hits and homers. The latter two issues are regressed in ERA estimators like xFIP and SIERA, which sit at 4.19 and 4.13, respectively. Also of concern is that Gsellman has faced a fairly soft schedule with two starts against Atlanta and three against Miami. An ERA just north of 4.00 would be acceptable from Gsellman going forward, but without strikeouts, he will be a liability on any fantasy squad.
Dansby Swanson (SS – ATL)
Also in week 1, I suggested trying to buy low on Swanson, citing solid batted-ball skills. Since then, things have not improved much for the young shortstop. Overall, he is hitting .174 with a .220 wOBA. His Baseball Savant xwOBA sits at .261 and expected batting average (xBA) at .194, suggesting he might have been somewhat unlucky, but not extraordinarily so. In fact, Swanson’s 2016 .242 xBA hints that his .302 AVG in 145 plate appearances may have been deceiving. While his contact rate has dropped from 77.9% last season to 71.6% this year, his BB% has ticked up from 9.0% to 10.3%. A nice walk rate alone does not a valuable fantasy player make. Owners in keeper leagues may want to hold on, but redraft owners can, and likely have already cut bait.
Rose-Colored Glasses
T.J. Rivera (1B/2B/3B – NYM)
Rivera reminds me of early-career Daniel Murphy from the right side. The utility infielder has shown an ability to make contact and, as long as his BABIP stays high, hit for a high average. Like that version of Murphy, Rivera has hit for modest power, with a .153 ISO and four career home runs (one this season). Rivera’s .247 xBA suggest that his .306 average will come down, perhaps settling near his .276 Steamer projection. Without a track record of power or speed, if Rivera cannot continue to maintain a .300 batting average, his fantasy value will be limited. An undrafted free agent, Rivera making the majors is a great story, but until he can start demonstrating an ability to generate hard contact, he is best left unowned in all but the deepest NL-only leagues.
Ben Gamel (OF – SEA)
Gamel does not appear to have any particular carrying tool. In the minors, his highest single-season home run total was 10. His 22 stolen bases in 2013 was also a career high. After struggling for two years in Double-A, Gamel hit for a strong average in 2015 and 2016 at the Triple-A level. His best attributes are considered to be his line-drive hitting approach and defensive versatility in the outfield. Filling in for the injured Mitch Haniger, Gamel has provided plenty of value with his bat, slashing .309/.427/.485 with two homers in 83 plate appearances. His 26.5% K% and 16.9% BB% are both higher than his minor league averages and are likely to stabilize closer to his Steamer projection of 21.6% and 8.3%, respectively. As is typical of a player with a .432 BABIP, Gamel’s average will likely drop toward his .271 xBA and his .257 projection. His value will also be highly playing-time dependent. With Haniger expected back by the end of May and Guillermo Heredia, Jarrod Dyson, Taylor Motter, and Leonys Martin all in the outfield mix, Gamel may not be worth a long-term investment.
Ian Happ (2B/OF – CHC)
Injuries to Kris Bryant, Ben Zobrist, and Addison Russell unexpectedly opened up a door for Happ to make his MLB debut over the weekend. While his three-game sample is too small to draw any real conclusions, he has produced two homers and a double and is already drawing speculation that he could stick around the big club. Fantasy owners may be tempted to hang onto Happ after his fast start, but Bryant and Russell have returned to the lineup, and Zobrist appears to be close. With Zobrist, Albert Almora Jr., Jon Jay, and Kyle Schwarber all in line for outfield playing time and not much more room on the infield, there just does not seem to be a clear path for Happ. His prospect pedigree and minor league performance make him an intriguing option when he does slot into the lineup regularly, but it may not be in the cards barring additional injury trouble.
Walking on Broken Glass
Dylan Covey (SP/RP – CWS)
As a young pitcher, but not one of the anointed future aces, Covey occupies a strange place in the White Sox pecking order. Coming to the south siders as a Rule 5 pick, Covey has displayed a full four-pitch arsenal, but little in the way of swing-and-miss stuff in the majors or minors. Strikeout and walk rates of 6.14 K/9 and 3.99 BB/9 in 29.1 innings pitched do nothing to dress up his 7.98 ERA and 1.88 WHIP. A 5.26 xFIP does suggest he may expect slighty better fortune going forward, but Covey is not a useable fantasy option at this point. With Carlos Rodon and James Shields injured and Reynaldo Lopez, Lucas Giolito, Carson Fulmer, and even Michael Kopech simmering in the minors, Covey seems to be little more than a real-life innings-eater on a short leash.
Matt Strahm (SP/RP – KC)
Left-hander Matt Strahm succeeded in a starting role in 2015 and 2016 in the minor leagues but made his major league debut last year as a reliever. He had success striking out batters and suppressing runs (12.27 K/9 and 1.23 ERA). His 4.50 BB/9, 0% HR/FB, and 84% left on base rate netted a 3.o4 xFIP, suggesting Strahm was good, but not as otherworldly as his results. Tapped to stay in the bullpen for 2017, Strahm really struggled out of the gate, walking six and striking out none in 1.1 innings, allowing seven earned runs. After nearly two weeks in the minors, Strahm was recalled and has yielded two earned runs in 11 innings with 16 Ks and five BBs, three of which came in his most recent appearance. Strahm’s lack of control in the majors is surprising given his low walk rates in the high minors. His curveball was graded as his best pitch in the minors, and it does have a well above average 2727 RPM average spin rate, but his changeup has actually generated a higher rate of whiffs (18.6% vs. 14.9%), and has not yet been put in play for a hit. If Strahm can begin to generate more swings out of the zone on both his offspeed offerings, he should be able to trim his walk rate and maintain his strikeout rate. While he currently sits in a middle-relief role, the Royals seem to view him as a potential high-leverage option in the future. With fellow southpaws Mike Minor and Travis Wood available to handle LOOGY duty, Strahm seems to have a clear path to the 7th inning role, and perhaps later, pending his performance as well as the health of Joakim Soria and Kelvin Herrera. Holds leaguers should keep tabs on Strahm as yet another potential high strikeout, late inning option.
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Andrew Dominijanni is a correspondent at FantasyPros. For more from Andrew, check out his archive and follow him @ADominijanni.
