Here's a situation: it's the ninth inning, your favorite team is up by one run, and the heart of the opposing team's order is due up. There are only two types of closers in this scenario - those who make your nervous, and those who don't. The list for the latter is a short one. I think it goes something like this: Kenley Jansen, Craig Kimbrel, Aroldis Chapman, Andrew Miller, a healthy Zach Britton, and...Roberto Osuna? Hear me out on that last one for a sec.
Below are the Fangraphs WAR leaders for relief pitchers from 2015-17. Osuna is tied for sixth. The rest of the group? The other five I named plus Dellin Betances.
I have to admit it's a little surprising to see Osuna there, but it shows this isn't just a first half of 2017 fluke. Osuna has been borderline elite for two and a half years now, and he's still getting better (ranking fifth in fWAR for relievers this season). Here's a great Jeff Sullivan FanGraphs blog about what has led to Osuna's continued improvement in 2017. One reason is A+ command of all his pitches. Another is the fact that he has mastered a pitch arsenal of a fastball, slider, and cutter.
It's rare to feature those three pitches together. This is because the slider and cutter are such similar pitches. They look exactly the same coming out of a pitcher's hand, but the slider has slightly less velocity with more of a vertical drop. It can be tough to throw both pitches so well because they often blend into the same pitch. However, if you can master the difference between these two like Osuna has, it's an incredible weapon to have.
Back in June Osuna was unavailable to pitch for a few days because of an anxiety issue he was dealing with. According to the closer himself he was feeling "anxious and lost". It's rare to see anyone, particularly a pro athlete, be this candid about a mental illness that for some insane reason still carries a stigma. But anxiety is a fucked up thing, particularly for a closer who's job requires having a short memory and not fixating on the past. Osuna didn't reveal much about what was causing his anxiety, but did mention that it was off-field related and that this was the first time he had experienced these symptoms. I'm no Blue Jays fan, but I'm certainly now an Osuna fan for how he's overcoming this. It clearly hasn't affected his on-field performance.
2017 has been an incredible year for relief pitching. Perhaps Osuna hasn't received much buzz because of how good Kimbrel and Jansen have been. Or perhaps it's because the Blue Jays haven't been a very good team. Either way earlier this year Osuna became the youngest pitcher ever to reach 75 career saves. He's still only 22!! Jansen received a lot of attention this year for taking forever to finally walk someone. He's now walked two batters. Osuna has walked just three. In 35 innings he has also struck out 47 with a 2.06 ERA and a 0.71 WHIP, becoming an All-Star for the first time this season.