With J.J. Putz‘s elbow hurting, the Diamondbacks have turned to Heath Bell in the closer’s role. Tuesday night against Atlanta, Heath Bell converted his fifth save in six last-inning save opportunities in impressive fashion: after the first baserunner reached on an error, Bell struck out Evan Gattis and Dan Uggla swinging before retiring Chris Johnson on a fly ball to center. Wednesday afternoon, Bell added another, as he worked another hitless and walkless inning, including a strikeout of Justin Upton.
Bell’s debut outing with Arizona looked like the beginning to another ugly season, as he allowed three runs on four hits (including two home runs) and managed just one out. Since then, Bell has been brilliant: over 18 appearances (17.2 innings), Bell hasn’t allowed a home run and has recorded 22 strikeouts against just two walks, good for a 3.06 ERA and a stunning 0.87 FIP. These two saves against Atlanta featured the drivers behind Bell’s success: impeccable fastball control, and the willing to go to it whenever he needs a strike.
In many ways, Heath Bell is a fascinating pitcher. His pitching motion is unorthodox. He’s something of a personality. And although Bell can throw his fastball for a strike at almost any time, his curveball is almost never in the zone.
Since 2007, Bell has thrown 4,476 fastballs with a 67.6 percent strike rate, nearly three points above the league average and better than roughly one in every eight big league pitchers. In 2013, and even in the fiasco of his 2012, Bell’s strike rate has climbed higher — 69.5 percent or better. His soft stuff, on the other hand, has never found the strike zone. His 59.5 percent strike rate is about three points below the league average and moving in the opposite direction. Last year, Bell threw strikes on just 51.5 percent of his 330 curveballs; this year, his strike rate has crashed below 50 percent.
The biggest difference between 2013 Bell and 2012 Bell has been the control. Bell’s two walks in his last 17.2 innings comes out to just over 1.0 BB/9, over three walks per nine innings less than last season. Given the massive gulf between his fastball control and offspeed control, the reason is intuitive: he’s sticking with the fastball more often in general, and specifically in hitters’ counts.
Bell is and has always been a fastball pitcher. He thrives on getting ahead in counts. When he was going well back in 2008 and 2009, Bell’s fastball even served as a sharp putaway pitch, as I detailed last year. His fastball’s whiff rate has declined steadily since 2010, as Brooks Baseball details here:
So Bell’s solution, both in 2011 and 2012, was to throw the fastball less frequently. Once his curveball control fell off the table in 2012, the strategy became untenable. Bell threw a curveball or changeup (which he had similar problems controlling) 43 percent of the time in pitchers counts in 2012 compared to 30 percent over the rest of his career. As a result, Bell lost most of those pitchers counts when the curveball missed the strike zone. He ended up with a career worst walk rate and just missed a career low strikeout rate by 0.7 percent.
This year, the fastball is back. He’s throwing it five percent more often overall and nine percent more often in pitchers’ counts. It still isn’t garnering swings and misses like it used to, but a 14.4 percent whiff per swing rate is still league average despite the decline — it’s workable, and certainly a better alternative than issuing free pass after free pass.
Additionally, Bell is throwing the fastball over 90 percent of the time on three-ball counts, by far the highest of his career. He has thrown half as many three-ball curveballs in 2013 as he did in 2012, and his walk rate has fallen similarly — 10 percent to 4 percent.
Will hitters readjust? They may have been looking for the curveball more often this year as a result of tape from 2011 and 2012, and if so, hitters could take advantage of a fastball that hasn’t shown the ability to miss bats it once had. However, Bell was dealing with mechanical issues earlier in the season, as he noted to the Arizona Republic‘s Bob McManaman after Wednesday’s save. His velocity has been trending up ever since his second appearance and has returned to the mid-90s over his last few outings. It will be worth watching if this regained velocity means the whiffs return as 2013 continues.
Kevin Towers left San Diego in 2010. Immediately afterwards, Heath Bell moved away from his bread-and-butter, strike-zone pounding fastball and moved towards his wild and inconsistent fastball. The result was two seasons suggesting his downfall from one of the game’s best closers to one of its biggest punchlines. Now, with Bell and Towers reunited, Bell’s fastball is flourishing again — and so is he.