Yankee Hitters So Far vs. Statcast Expected Performance

After tonight's game, the Yankees will have crossed the halfway point in their season. Coming into this season, most projection systems were expecting the Yankees to finish below .500 for the first time in over two decades. The future was bright, the Yankees had one of the best farm systems in baseball, but other than Gary Sanchez, didn't seem to have arrived yet. 

Things have changed. The Yankees spent most of the first half as the second best team in the American League, division leaders, and performing great all over the roster. Around the beginning of June, things began to change. Aaron Judge and Gary Sanchez remained hot, but the rest of the roster struggled. Now, the Yankees are 2 games behind the Red Sox for first place in the American League East, with their own two game lead in the wild card race. 

What happened? Injuries are only part of the story. The Yankees were losing before Holliday, Castro and Hicks went down. Other than Adam Warren and CC Sabathia, their pitching staff is perfectly health.

Instead, I think the Yankees were met with some good old fashioned regression to the mean. Other than Sanchez, Judge, and Holliday, a lot of players were performing way above their expected performance level. Below is a table with three statistics: each Yankee hitter's wOBA so far in 2017, their projected wOBA by Steamer, and their xwOBA from Statcast. xwOBA takes the measured exit velocity and launch angle of batted balls for each player, plus their strikeout and walk rates, and estimates the expected value of those batted ball events:

Aaron Judge0.4750.3310.454
Gary Sanchez0.3910.3480.398
Matt Holliday0.3770.3530.369
Aaron Hicks0.3930.3130.338
Brett Gardner0.3470.3220.325
Starlin Castro0.3620.3080.31
Austin Romine0.2720.2920.307
Chase Headley`0.3190.3150.307
Jacoby Ellsbury0.3170.3080.296
Chris Carter0.2910.3480.292
Didi Gregorius0.3530.3080.268
Ronald Torreyes0.3070.2940.261

Let's start by comparing the wOBA column with the projected column. Judge, Sanchez, Holliday, Hicks, Gardner, Castro and Gregorius have all well outperformed their projected wOBA so far this season. Only Carter and to a lesser extent Austin Romine have underperformed. That's the difference so far between the projection systems' high-70s win projection and the team's current 87-win pace.

There are two reasons why players deviate from their projects: they could perform better than expected, or they could be getting lucky on batted balls. We now have xwOBA to settle that mystery. Aaron Judge and Gary Sanchez, and to a lesser extent Matt Holliday, are judged by xwOBA as the real thing. To no one's surprise, Judge's batted ball profile suggests he has been an MVP-level hitter. Gary Sanchez has built on last season as well. We knew that.

Gardner, Castro, and to some extent Ellsbury and Headley  have clearly benefitted from some batted ball luck, with xwOBAs matching their projections. Aaron Hicks' xwOBA beats his projection, but falls well short of the near-MVP performance he has put up so far this season. He's hitting like more of an above-average player, which is still pretty good for someone with his defensive skills.

The real bad news here is Didi Gregorius, who has clearly gotten very lucky on the season. Gregorius was never much of a hitter, so it makes sense that his breakout has been too good to be true.

How Good Are the Yankees Really?

The team as a whole averages out to a 0.329 xwOBA. That's really good! The average team has about a 0.315 xwOBA so far this season. Gary Sanchez and Aaron Judge are indeed superstars, and can elevate an average supporting cast to a playoff spot. It is not, however, world-beating. The Yankees have a wOBA is 0.344 this season. Going forward, they can expect to regress back to their (solid) expected performance.

Problem is, the Yankees aren't going to win 95 games with a 0.329 wOBA, especially with their only above-average (3.96 FIP) pitching staff. 87 wins seems about right to me. The Yankees are good enough to compete with the Rays, Angels, Blue Jays, Royals and Twins for a wild card spot, but not good enough to hang with the Indians, Astros and Red Sox over a long season.

Bottom Line: It's a House Money Season

Because our hopes were raised, it feels really bad to lose so many games in June. The Yankees looked like a powerhouse in April and May. However, it's easy to forget that 87 wins would be a huge surprise given the preseason projections. Severino, Judge and Sanchez are proving to be the beginnings of a core Yankee team that can be the best in baseball. Jordan Montgomery might be in there as well. Castro, Gardner, Gregorius, Ellsbury, Pineda, Sabathia, and the rest are a fine supporting cast, but not one that makes them a World Series favorite,