Should we believe Fantasy Baseball's most surprising hitters at halfway mark?

Chicago Cubs’ Javier Baez has been one of fantasy’s biggest success stories this season behind a mix of power and speed. (AP Photo/Chris Carlson)
Chicago Cubs’ Javier Baez has been one of fantasy’s biggest success stories this season behind a mix of power and speed. (AP Photo/Chris Carlson)

With the season at the halfway point, let’s look at the most surprising positive hitting values, according to TGFantasy’s calculator (12-team mixed league, $260 budget, 33% on pitching). Most of the stats courtesy of our friends at MLB stat provider Inside Edge.

Evan Gattis is the second best catcher with $19 earned and that’s despite hitting .200 through April. He’s pulled all of his homers, which makes up for an overall well-hit average of at bats that is not good — .135 vs. league average of .148. Gattis has been terrible at home with an OBP of just .235, including a .173 average. It’s amazing how underrated a pitcher’s park Minute Maid is. Gattis is such an extreme fly ball hitter, with just 33.1% grounders divided by grounders plus flyballs (league average is 57%). Gattis is dead red, too, slugging .669 on fastballs. He clearly has a lot of holes and can be pitched to. This level of production is thus unsustainable. I know he’s a catcher who doesn’t catch but if he runs ice cold for a few weeks, which is 50/50, he’ll lose playing time. The Astros aren’t screwing around.

Jesus Aguilar is earning $33 despite struggling for playing time early in the year, when we wrote about pouncing if he somehow got into the lineup regularly. He’s an A-minus hitter according to Inside Edge only because he chases more than the league average. But the .232 well-hit average is A+, trailing only Mookie Betts, J.D. Martinez and Mike Trout. Aguilar’s OBP with two strikes is .341 where league average is just .250. And his OPS with two strikes is .865, which leads MLB and is over 300 points better than average. Other leaders are Nolan Arenado, Brandon Belt and Trout. Aguilar is a real hitter. He hit last year. He’s a hold if you’re lucky enough to own him.

Scooter Gennett is at $31. HIs batting average leads the league, as does his .355 on grounders (average is .250). The only hitters with a higher average on grounders are Addison Russell (.403), Betts and Jean Segura. For comparison’s sake, Matt Carpenter is .085 (last). Gennett is not a sabermetric darling by any means, drawing just six walks against starting pitchers, a rate that’s third lowest (Dee Gordon and JaCoby Jones are worse). He’s also chased 52.7% of pitches out of the zone (avg. 40.5%), ninth worst. Gennett’s well-hit is also only about average (.154). The combination of ground-ball luck, lack of plate discipline and a ho-hum well-hit rate scream that he’s greatly overachieving. But I feel like I’m going broke fading Gennett. The data says to fade him though.

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Ozzie Albies is at $27. He has the highest rate of swinging at low fastballs, so maybe that’s an adjustment waiting for pitchers to exploit. Albies is just a B-minus hitter. He’s doing poorly with two strikes and with plate discipline. His well-hit is .171 though, which is solid. That speaks better of his power than Gennett’s, for example. But my argument for Albies since the winter was that he’s so young that what he’s doing is historic. It was true then and true now. Looking at hitters with 600+ PAs age 20-21, Albies has a 118 OPS+ (100 is exactly average) and Hank Aaron’s was 125 (these numbers are all adjusted for era and park). Albies is beating the same age OPS+ of future HOF outfielder Lloyd Waner (109) and middle infielders Cal Ripken (107) and Roberto Alomar (106).

Javier Baez at $32 shocks me. I thought maybe he’d be a nice $20 placeholder without much upside given some holes in his swing and questionable playing time. But the steals have lifted him into the fantasy stratosphere. Baez’s well-hit is .202 and he’s just pounding fastballs (.346 average against). His plate discipline still grades an F with 12 walks and 73 Ks. It’s hard to bet on a guy continuing to be great in fantasy when that weakness is this pronounced. But if he keeps stealing, he’s going to do enough other stuff to maintain this approximate value. And he’s 13-for-14 on the bases. Another key is going to be where he hits. Baez has most of his PAs batting second and a .995 OPS there (.338/.348/.646). But he’s all over the place, with 60 PAs batting seventh (.820 OPS) and 50 batting eighth (1.047). Joe Maddon just can’t leave well enough alone. His best base running slot though is seventh: six bags compared with just two batting second. This makes sense because you can be more aggressive running in front of weaker hitters.

Eddie Rosario at $32 is perhaps fantasy’s biggest surprise. He’s an A-minus hitter, according to Inside Edge, with red ink (that’s good) all over his report card. While his plate discipline is a D+, he strikes out on only 32% of two-strike counts (MLB average is 40%). Rosario has just three walks in 75 PAs with runners in scoring position. But that’s good for us. Rosario’s walk rate with RISP of 4% rate is third lowest. Note teammate Brian Dozier is 4.2%. You’d much rather have a guy swinging with runners on unless you are in an OBP league. Compare Rosario’s rate to Trout (30.4%), Michael Conforto (27.3%) and Bryce Harper (26.6%).

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