Hector Rondon has yet to receive the number of save opportunities to prove he is worthy of being mentioned among baseball’s best closers, but he has not needed them because he has done so much more to show how dominant he has become as a late-inning reliever.
Specifically, he has become a strikeout machine en route to dominance in his 16 appearances. And over at MLB.com, Mike Petriello notes two major developments in Rondon’s ascent to dominance.
First, Rondon has challenged more batters with more strikes. as only five pitchers have a higher percentage of pitches in the strike zone than Rondon’s 57.6 percent. Next, Rondon has received a boost in called strikes as batters are swinging at only 41.5 percent of his pitches. Combine those two things and you get a lot more strikes.
Further, it’s not like Rondon has added a totally new pitch or increased his velocity significantly, but he has done this:
Rondon has always found significant usage of his four-seamer, but the most intriguing development might be in following his slider usage which saw double the action in 2015 than it did in 2014. His use of the slider went from 16.72 percent in 2014 to 36.08 percent in 2015 before settling at 36.78 percent this season.
The slider has been an effective swing-and-miss pitch over the last two seasons for Rondon. Whether it is down and away from right-handed batters or down-and-in to lefties, it has produced a significant number of whiffs.
That is a ton of red in the lower right-hand corner and that is precisely what Rondon and the Cubs want to see when that pitch is deployed, especially in high-leverage situations.
As Michael already pointed out, Rondon’s career trajectory has been an atypical one, but one that features equal parts good fortune for the Cubs and quality work ethic from Rondon as he bounced back from several arm injuries that derailed his career as a prospect in the Indians organization.
At this point, the next step for Rondon is actually getting into high-leverage situations to show off the goods. Unfortunately (for him) those chances have been few and far between.
Give Petriello’s article a read for more on the Cubs’ dominant closer.