Several players on the Yankees have hit decidedly better or worse than most expected in the preseason. On the unexpectedly good side, there’s Yangervis Solarte, who’s emerged from minor league obscurity to post a 119 wRC+. Meanwhile, Carlos Beltran, Brian McCann, and Alfonso Soriano all have wRC+’s in the 70’s, and have all fallen well short of what we’ve come to expect based on seasons past. Yet despite their first-half performances, the projection systems haven’t budged all that much on these players since the preseason. Per Steamer and ZiPS, each is only expected to retain around 10-20% of the deviation from his preseason projection. In other words, the projection systems think these guys’ future wRC+ will be five to ten times closer to their preseason projection than to their current mark.

Mitchel Lichtman, more colloquially known as MGL, crunched some numbers to see if a player’s year-to-date stats can tell us anything that the projection systems are missing. To conduct his analysis, he used an in-season projection system, not unlike the ones used to create the graphic above. In a nutshell, he found that the in-season projections did a pretty good job of predicting future performance — even for players who were hitting much better or worse than anticipated. “Hot” players may be slightly more likely to out-hit their projections in the future, but only by a few points of wOBA. For the most part, projections do a fine job of baking recent performance into their final outputs.
When trying to anticipate future performance, your best bet is basically to just trust whatever the projection systems say, even if your gut tells you otherwise. In most cases, a player’s numbers from here on out will be similar to what’s on the back of their baseball cards, regardless of what’s happened in the last month or two. This bodes well for established players like Beltran, McCann, and Soriano, who have successful track records, and can probably be expected to bounce back to at least some extent. Unfortunately, it also suggests that Solarte might still be the forgettable player we thought he was three months ago — regardless of what’s happened since.
Statistics courtesy of Fangraphs; Projections are an average of ZiPS and Steamer