The 2017 Yankees were a lot of fun, but 2017 Dellin Betances was not. Sure, he had a 2.87 ERA, but his wildness (I mean, the man was literally walking more than six batters per nine) and unreliability, especially in the later months of the season, led Joe Girardi to banish him from the circle of trust in the playoffs. Coming into the 2018 season, it was a total mystery whether we would see Good Dellin or Bad Dellin for most of the time.
Two months into the season, it's still too early to tell whether the Betances of old is back or is still lost. However, the early signs have been encouraging. The numbers suggest that while Betances has been unlucky in terms of home runs, he's been able to dial back his wildness while maintaining his strikeout ability.
First, let's get the bad stuff out of the way. Betances has been unusually homer-prone in 2018, having allowed 4 long balls in 27 inning pitched. That's one more homer than he allowed in all of 2017, and the same number of dingers he coughed up during his 2014 breakout year, in which he threw 90 innings. One of Betances' core skills was limiting homers; however, that skill has apparently deserted him in 2018.
Or has it? While it's true that Betances has allowed more home runs this year than last year, he's also been more effective at limiting fly balls. So far in 2018, Betances owns a fly ball rate of 26.4%, compared to a 38.1% mark in 2017. In addition, it's not like he started giving up tons of hard contact, as his 26.4% hard hit rate isn't too far off from his 25.2% career mark. Nevertheless, 28.6% of the fly balls that Betances has allowed have gone over the fence, in contrast to a 7.5% rate in 2017.
This, to me, smells more like bad luck than a decline in skills. HR/FB is a particularly fickle stat with little to no correlation between seasons, and has been shown to fluctuate around league average over time, which is generally around 9% to 10%. Given that knowledge, we can expect Betances' homer rate to regress towards the mean in the future. Sure, maybe Dellin was ambushed four times by batters ahead in the count sitting dead red fastball. The same thing might happen from time to time in the months ahead, but I'll bet it won't occur with the same frequency.
Now, onto the good stuff. Rejoice, Yankee fans; Dellin has brought down his walks per nine under 4, and is currently sporting a 3.67 mark. Meanwhile, he's striking out 15.33 batters per nine innings, which is the second-highest mark he's ever run, trailing only his 2016 K/9 of 15.53. Betances' peripheral numbers support his gaudy strikeout numbers as well, as they show that he's coaxing more swings out of the zone (29.1% O-Swing rate in 2018, compared to 23.6% in 2017) and generating more whiffs (13.3% swinging strike rate in 2018, 12.7% in 2017) than last year. Dellin has dialed back his wildness while retaining his effectiveness. What more could we ask of him?
In sum, Betances has been both unlucky and good so far this year. He's been unlucky because the fly balls he allows are going over the fence at a higher rate than usual this year, but that should sort itself out going forward. Meanwhile, Betances has been able to cut down on his walks while still striking everybody out, and his peripherals suggest that that should continue. It may still be early, but count me among the “Dellin is back” camp. If you're curious, we're still accepting registration.