With an earned run average approaching six in his first eight innings of work, the month of April was not too kind to Toronto Blue Jays’ closer Roberto Osuna. Batters hit over .300 against him and he blew three of his first six save opportunities. His batting average on balls in play spiked up to .375 during that time and he didn’t walk any batters either, so it’s possible luck may have been against him. In any case, it was definitely the roughest stretch of Osuna’s young career when factoring in where he left off at the end of the 2016 season, both in terms of runs allowed and hits allowed as the charts below show.
Whether luck had anything to do with it or not, Osuna has since turned it around completely, allowing a total of three runs over his last 18 innings pitched in May and thus far into June. He’s also converted 12 consecutive saves, bringing his total to 17 on the season.
His consecutive save streak really indicates the high level of performance Osuna’s had since the start of May. During that streak he’s allowed two runs on six hits over 10 2⁄3 innings with 16 strikeouts. He’s also only walked one batter in that stretch and actually hasn’t walked a batter in his last nine appearances. Not to mention that in 10 of the 12 saves, he had 2 or less days of rest and has an average leverage index approaching 2.0 over those 12 saves. So it’s an understatement to say Osuna’s been challenged and is nonetheless pitching as well as one could expect.
A few adjustments Osuna has made during the months of May and June have been largely responsible for his recent success. First, he adjusted the usage on his twoseamer from almost 30 percent in April down to about 11 percent since, which caused him to increase his fourseam and cutter usage. More importantly, his slider usage has come up slightly, just a few percent points, with almost immeasurable success as a result. Comparing his current pitch usage to that of the 2016 season, he’s mixing in more cutters and sliders with fewer changeups and fourseam fastballs.
Osuna’s Pitch Usage
|Usage||April||May & June||2016|
|Usage||April||May & June||2016|
According to Statcast, Osuna had 10 called strikes in the 37 twoseamers he threw during the month of April but he also threw 12 balls, good for a 32.4 percent ball rate. The average exit velocity on the twoseamer is only 84.7 miles per hour, so it wasn’t hit very hard and only resulted in two hits. But even when considering that, it’s hard for him to justify returning to a high usage of the twoseamer with the success he’s had since supplementing it with his fourseamer.
I haven’t mentioned his changeup usage, which has also decreased quite a bit since the beginning of May. In April he threw 10 changeups total with mild success, recording three strikeouts using the pitch. However, since May 1st, Osuna has thrown just six changeups, all of which were balls outside of the zone. So it seems lately Roberto doesn’t have a good feel for the changeup or at least hasn’t found many appropriate situations to use it in.
In decreasing the usage of his change up, Osuna has increased his slider usage which has produced significant results. Osuna has recorded 20 strikeouts with his slider this season, only one of which occurred during the month of April. That means he has 19 strikeouts in the months of May and June while using the slider in 39 different plate appearances. That comes out to a 48.7 percent strikeout rate!
Diving deeper, Osuna had seven swinging strikes in the month of April over a total of 30 sliders thrown, a 23.3 percent whiff rate. He has 29 swinging strikes in the months of May and June out of a total of 70 sliders thrown, which comes out to a blistering 41.4 percent whiff rate, almost double what it was in April.
His cutter also seems to be benefiting from the adjustments during May and June as he’s recorded eight swinging strikes in 36 total cutters thrown which is just over 22 percent. He only had two swinging strikes in the 15 cutters he threw during the month of April, which comes out to a little over 13 percent.
But usage rates aren’t the only thing that have salvaged Osuna’s season. He’s also adjusted the pitches that he throws in specific counts. As you can see in the chart below, Osuna has relied heavily on the slider in various counts over the last two months, especially in strikeout counts. That, coupled with the decrease in twoseamers overall since the start of May, has really allowed him to bounce back.
Although the change in fourseamer usage hasn’t changed his called strike or whiff rates by more than two percent, he has five strikeouts in the months of May and June with his fourseamer versus only one in the month of April. This tells me the increase in strikeouts on the fourseamer is mainly due to the sequencing of his pitches.
Also notable is that, during April, Osuna primarily used the cutter in almost any count with a few exceptions. Since the start of May he’s only using it early and ahead in the count, except in 3-0 counts. This allows him to go back to the four seamer or slider for the strikeout. Additionally, the changeup is almost non-existent as far as usage, so it’s evident the changes in usage especially in specific counts has benefited Osuna.
Further evidence that Osuna’s success is based on the adjustments he made is the fact that he has decreased his percentage of pitches in the strikezone while simultaneously seeing a steady increase in his out of zone swinging percentage. In other words, he is fooling hitters more with pitches out of the zone, since he’s throwing more pitches out of the zone and getting a greater swing percentage on those pitches. This is aiding in his swing and miss numbers and as a result has increased his strikeout percentage from 23.5 percent in April all the way up to 40 percent since May 1st.
Since breaking into the league in 2015, Roberto Osuna has always been a reliable closer with high-octane strikeout stuff, and since making the adjustments he has thus far, it put him right back on track with what he’s done in his previous two seasons. I’d even go as far to say he’s even better now than he was at any point previously in his career, since he’s shown a clear ability to adjust to negative performance.
After turning it around at the beginning of May, Osuna is back among the best relievers in baseball. Only one relief pitcher has a lower walk rate than Osuna and that is the Dodgers ultra-closer, Kenley Jansen. Roberto’s also among the top 15 relievers league-wide in field independent pitching, wins above replacement, walks & hits per inning pitched. If Osuna is able to continue the dominate stretch he’s currently on, look for him to put up some spectacular numbers by the seasons’ end and definitely finish among baseball’s best relievers for a third year in a row.
Ron Wolschleger is a Contributing Writer for Beyond the Box Score as well as Bless You Boys. You can follow him on Twitter at @FIPmyWHIP.