Yu Darvish’s Stellar Return Puts Texas in Position for October

Here’s the good news: the Texas Rangers have the best record in the American League and a seven-game division lead. Here’s the less-good news: our playoff projections give them roughly one-in-10 odds of relinquishing their division lead before the end of the season due, in part, to the worst rest-of-season winning percentage projection of any current first-place team. One of the primary reasons projection systems are down on the Rangers relative to other first-place teams is that they’ve struggled with run prevention this season and a key cause of that struggle has been their difficulty filling out a five-man rotation with healthy, reliable starting pitching. However, the top of their rotation features a stealth Cy Young candidate in a weak field, Cole Hamels, and an ace who is increasingly looking like another Tommy John success story: Yu Darvish.

Since rejoining the rotation for good after the All-Star break, Darvish has been among the best pitchers in the American League on the strength of a 2.70 ERA, 3.32 RA9 and a major-league-leading 28.0-point strikeout- and walk-rate differential (K-BB%). But one of the most encouraging things to see with Darvish is that he’s been able to go deep into games. It wasn’t until his most recent two starts that he crossed the 95-pitch threshold this year, and yet he’s currently riding an active six-game streak of going six innings or more in his starts. Things have been going extraordinarily well of late for Darvish and it’s worth taking a look at what has and hasn’t changed for Darvish and whether or not he’s truly “back.”

One of the biggest myths about Tommy John Surgery (TJS) is that it will increase a pitcher’s velocity. There is no evidence that there’s truth to this theory. However, there are anecdotal examples to which can one can point, and right now it looks like Yu Darvish may end up being one of those cases. According to Brooks Baseball, the average velocity of Darvish’s four-seam fastball is currently up nearly one full tick on his previous career high.

It should be noted, though, that as Darvish’s season has progressed (and his pitch count per game has increased), his velocity has consistently been trending back in the direction of his previous norms.

The gradual stabilization of his velocity has had no significant negative impact on his results. He’s been tremendous so far in the month of August, posting a gorgeous 31:3 strikeout-to-walk ratio over 27 innings. One of the biggest improvements for 2016 Darvish over his pre-TJS self has been a dramatic improvement in his ability to limit base on balls. He entered the season with a career 9.6% walk rate but has walked just 5.9% of batters faced so far this season. The question as to whether or not this is a sustainable improvement is a good and, perhaps, unanswerable one; but with a change for the good like this, it always helps to see a corresponding change in approach and Darvish certainly has shown that this season.

In prior years, Darvish wasn’t afraid to go to his secondary offerings on three-ball counts. This year, however, he’s shown an increased reliance on fastballs in those situations. First, let’s take a look at Darvish’s pitch selection on three-ball counts prior to the 2016 season using a chart generated on Baseball Savant:

Notice the frequency with which Darvish went to the slider (SL) or cutter (FC) in those situations. Meanwhile, he used his four-seamer (FA) and sinker (FT) a bit under half of the time. Now let’s take a look at his pitch selection this year:

This year, Darvish has upped his usage of his four-seamer or sinker in three-ball counts to nearly three-quarters of the time while slashing his slider and cutter usage nearly in half. Whether a direct result of this shift or not, Darvish has induced a phenomenal .637 opponents OPS against in three-ball counts this year — well below the .988 league average OPS in those situations.

This success in fastball-heavy counts brings us around to another impressive thing about Darvish this season: he’s generating whiffs with his fastball at a tremendous rate. This isn’t an entirely new development — he’s always been good at making batters swing and miss — but this year, the whiff per swing rate on his four-seamer is 32.5% which is second only to Rich Hill among starting pitchers and represents the first time Darvish has crossed the 30% threshold.

Yu Darvish was a great pitcher pre-TJS and it certainly looks as though he’s on track to be a great pitcher post-TJS as well. While it’s not the most surprising development in baseball this season, it’s one that could have a tremendous impact on postseason baseball. Once October rolls around, the Rangers’ lack of a dependable fifth starter will become largely irrelevant and their weakness at the fourth-starter position will be dramatically less significant.

Although there’s no magic formula for winning in the postseason (that we know of) there are established paths to success and one of them is stellar talent at the front of the rotation. Hamels and Darvish may not quite be Randy Johnson and Curt Schilling, but they are front-of-a-rotation arms which any postseason team would feel confident in throwing out there in Games 1 and 2 of a postseason series. Combined with a solid offense which has been reinforced by the additions of Carlos Beltran and Jonathan Lucroy, it looks as though the Rangers could be in a better position to succeed in the postseason than they are in the rest of the regular season. Time will tell whether that will be enough to push the team to their third World Series appearance this decade.