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 current as of the All-Star break, and, as noted in week 3, any quoted Statcast numbers are directly from Baseball Savant.
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Rookie All-Stars
Both have been visited in multiple Rookie Reports, but All-Star week seems a good time to renew our appreciation for Aaron Judge and Cody Bellinger, the only two rookies to make their respective All-Star rosters. Judge (101 mph) sits first and Bellinger seventh (98 mph) in average exit velocity on line drives and fly balls among hitters with over 100 batted balls. Both are slugging over .600, and while Judge’s .426 BABIP has him hitting .329, Bellinger’s .261 average has been much less helpful. No qualified player in history has ever had a K% higher than 29% and hit over .300 in a season. The closest analog being Chris Davis in 2013, who struck out 29.6% of the time and hit .286. Incidentally, Bellinger would rank 11th on the list of highest batting averages with a K% over 29% should his current rates hold. Clearly, we are in an age of high-K power hitters providing big league value, but we still have not observed a true high-K, high-AVG slugger who can maintain a pace like Judge’s. While Judge’s average exit velocity is an outlier even in this exit velocity era, the safe money would still be on his second half average falling well below .300. Judge had over 500 plate appearances in all of his minor league seasons and his split season last year, but there is surely a chance that he could wear down in his first full big league season. This, combined with some reasonable regression, may be a signal for Judge owners in re-draft leagues to try to make a blockbuster sell-high trade. It would be a bold move, but Judge’s value may never be higher, especially after his dominating Home Run Derby performance.
Speaking of Yankees outfielders, Clint Frazier entered this season ranked ahead of Aaron Judge on the FantasyPros Consensus Prospect Rankings at 23rd overall, and with an equivalent 55 future value according to Eric Longenhagen. He likely would have been ahead of Judge in Bobby Sylvester’s rankings too, if Judge had still been deemed a prospect for the purposes of that list. For all his prospect status, Frazier failed to put up big numbers at any stop in the minors between the Cleveland and New York systems. While he had an OPS over .800 at both High-A and Double-A, he struggled mightily after promotion to Triple-A last year. On the rosier side, Frazier has always been young relative to his level, especially in Triple-A as a 21-year-old. According to Longenhagen, his good bat speed and raw power fight at times with his noisy swing, which shows in his 24.8% K% and modest .272 average in the minors. So far, though, Frazier has taken the majors by storm, hitting three homers in seven games and playing walk-off hero. As has been noted (speculatively) by players recently, the possibility of the MLB baseballs behaving significantly different from minor league balls may be contributing to the success of call-ups above and beyond their expected power performance based on minor league track record. While it is likely too early to count on this as a real trend, it is at least a suspicion that should lead us to consider rostering pedigreed prospects with questionable projections more seriously than in the past. Further, with Aaron Hicks and Matt Holiday on the DL, Frazier should play nearly every day. Although little in his minor league performance record suggests imminent major league value, fantasy owners with flexible rosters should consider rolling with Frazier until he shows that he is overmatched at the level, or until he is displaced by a returning veteran.
Stop me if you’ve heard this before. Unheralded late-round draft pick is a surprising major league debutante for the Saint Louis Cardinals and immediately produces. Jeremy Hazelbaker, Matt Adams, Tommy Pham, Matt Carpenter, and last week’s Rookie Report star Paul DeJong are just a few who fit the description and have gone in different directions long-term. Luke Voit is the latest in the line, having failed to register on any major prospect list since being drafted in 2013 with a 22nd round pick. Undeterred, Voit was demolishing Triple-A this year with 12 homer and a .967 OPS coming off a surprisingly strong 2016 campaign at Double-A where he was 45% better than league average. His Triple-A numbers may be slightly inflated by the hitter-friendly environment in the Pacific Coast League, but his production was still 49% better than average. Like Frazier, he sports a 25% HR/FB rate in the majors after posting rates around 14% in the high minors. It all adds up to three homers in 14 games with only a 17.1% K% and .316 AVG. He sports an outstanding 98.1 mph average exit velocity on liners and flies, and his high contact rate helps him achieve a 14.6% Barrels per plate appearance rate which leads all players with at least 30 batted balls. Unlike Frazier, who is feasting on 65.2% fastballs, Voit has seen a very average rate of 56.3% fastballs. Sure, Voit is likely to be closer to a league average player in the majors going forward, but there may just be some value in the 26-year-old’s bat, at least until Kolten Wong returns to push Matt Carpenter back to first base against righties. As Voit can only play first in the NL, he is likely to get squeezed out of full-time at bats.
I won’t devote too many words to a backup catcher, but Austin Barnes‘ performance has sustained long enough to deserve mention. The first thing to note about Barnes is his unusual catcher/second base eligibility combination, a testament to his defensive instincts and athletic versatility. As he did in the minors, Barnes has displayed good contact skills this season (4.6% SwStr%) and a patient approach (15.1% BB%). Most surprising his that he has found a credible power stroke and continued to display speed, with five homers and four steals in 126 plate appearances. His .368 xwOBA suggests he has been a little lucky on balls in play, but his solid approach and bonus speed should put him firmly on owners radars as a second catcher, despite his limited playing time behind Yasmani Grandal.
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Andrew Dominijanni is a correspondent at FantasyPros. For more from Andrew, check out his archive and follow him @ADominijanni.
