Who Are Baseball's Biggest Statcast Underachievers?

These three players haven't gotten the results they've wanted so far this season, but they're doing everything else right.​

Earlier this week, I wrote about three players whose numbers have been better than their Statcast data implies.

Naturally, there are also players at the other end of the spectrum, who have been making quality contact without the results. As mentioned on Tuesday, Andrew Perpetua’s expected weighted on-base average (xOBA) does a better job of predicting future wOBA than past wOBA, which helps us figure out which hitters could be due for a hot streak.

Here are the three players with the biggest gap between their xOBA and wOBA in 2017.

Manny Machado, Baltimore Orioles

Actual wOBA: .309

Expected wOBA: .371

Difference: -.062

Manny Machado is having the worst season of his big league career, but his exit velocity and launch angles certainly suggest randomness is the cause rather than a decline in his skills.

We could probably, at least partially, deduce this without the help of Statcast, seeing as his BABIP is .233. Plus, his .212 ISO is higher than his career average of .195 and his 9.5% walk rate would be the second-highest of his career is sustained through the end of the regular season.

His 14.1% line-drive rate seems troubling, but line-drive rate is the least reliable of the three ball-in-play types. Also, as Tony Blengino of FanGraphs notes, Machado has crushed the line drives he has hit but has gotten somewhat unlucky on them. The third baseman's average line drive has left the bat at 101.8 miles per hour, second only to Aaron Judge among the 315 big leaguers who have at least 20 line drives per Baseball-Savant.

Unfortunately for him, he is 284th in this group in terms of BABIP on line drives (.535) and tied for 124th in wOBA (.707). We should expect Machado to hit more line drives going forward and get better production on them.

Among the 274 players with at least 100 balls in play, Machado ranks eighth in exit velocity (92.9 mph). He also ranks ninth in terms of percentage of balls in play hit above 95 miles per hour (51.1%) and 16th in percentage of batted balls that were barreled (14.0%), which is the perfect combination of exit velocity an launch angle that would produce a .500-plus batting average and 1.500-plus slugging percentage.

His batted-ball profile isn’t perfect -- Blengino also notes his pop-up rate is a standard deviation higher than the mean (as of Tuesday) and that he is pulling too many ground balls. Still, the level at which Machado has been abusing baseballs suggests his actual to-date numbers should be better. There is no reason to expect they won’t be going forward.

Nicholas Castellanos, Detroit Tigers

Actual wOBA: .312

Expected wOBA: .370

Difference: -.058

Last season, Nicholas Castellanos had something of a breakout, hitting the ball with enough power to overcome bad strikeout and walk rates, along with poor defense to approach the 2.0-WAR threshold (he came up just short, but still had a 119 wRC+ and .350 wOBA).

He has hit the ball even harder in 2017, but the results have gone in the opposite direction.

Castellanos had an average exit velocity of 89.4 miles per hour last year, and it's at 90.3 mph this year. This is evident on grounders (84.0 mph vs. 80.7) and line drives (95.1 vs. 94.1), which are driving his .349 xBABIP (his real BABIP is .302)

He posted a .345 BABIP last year, which outpaced his .323 xBABIP. The bulk of his expected production last season came in the power department, where he posted a .274 xISO (and a .212 real ISO).

His xISO has fallen to .237 this year, thanks in part to a 33.2% fly ball rate that is nearly seven percentage points lower than his mark from 2016, while his average launch angle has fallen from 16.9 degrees last season to 12.1 degrees in 2017.

Still, his xISO is 61 points higher than his actual ISO, as his 95.2 mph exit velocity on fly balls is tied for 23rd among the 287 players with at least 50 flies.

Castellanos has struck out on nearly a quarter of his big league plate appearances, has a 6.5% lifetime walk rate and owns a -12.9 UZR/150 rating at third base, so his future value is dependent on his production on contact regressing to what Statcast says it should be.

It might be worth a gamble for fantasy baseball players, though. While you will not find Machado on your fantasy league’s waiver wire, Castellanos might be there, who is available in two-thirds of Yahoo leagues.

Todd Frazier, Chicago White Sox

Actual wOBA: .318

Expected wOBA: .372

Difference: -.054

Is there something about third basemen that make them underperform relative to their batted-ball authority? Probably not, but Todd Frazier is another player on this list who mans the hot corner.

After two seasons worth of production that was more or less in line with what Statcast said it should be, Frazier has severely underproduced in 2017. This is unfortunate for him, since his xOBA this year is higher than it was in both of the previous two campaigns we have on record.

Frazier has been plagued by a .219 BABIP, which will obviously regress going forward, but not all the way up to .300 like we learned in SABR 101. His xBABIP is actually just .268, which is in line with his .274 career mark, so this should probably be the ballpark we expect him to be in going forward. This makes sense, given that he is tied for the 16th-highest infield fly rate in the majors and has a below-average line drive rate.

Still, this regression we expect would mark a 50-point BABIP increase.

His xISO is also 53 points higher than his real ISO. His isolated power this year is around his career rate of .210, but over the previous two years, he had a .241 mark, so it is not unreasonable to expect him to improve his power output.

If Frazier can maintain his to-date batted-ball authority (and 13.9% walk rate), there is little reason to doubt he will provide well above-average value with his bat in the second half.