MINNEAPOLIS -- Blake Treinen may be rolling with Train on the back of his A's jersey for Players Weekend, but a niche portion of the baseball world has come to recognize him by a different nickname this season.
Treinen has been dubbed the Witch by Rob Friedman -- also known as the Pitching Ninja -- due to his knee-buckling repertoire of pitches that often leave hitters looking silly.:: Players' Weekend presented by Valspar Stain ::
Friedman, a pitching coach who tweets out a barrage of baseball's craziest pitches each day, has had plenty to post about on Treinen's behalf this season and has taken a particular liking to the Oakland reliever's turbo sinker.
"I think [Friedman] is doing a good job of appreciating different people's talents," Treinen said. "I guess I'm just lucky enough to be a part of it. … I'm not super into the whole social media, but it's pretty cool what he's able to do."

The sinker has helped Treinen become one of the more dominant relievers in the Majors this season and viral sensation. But it's also been bolstered by the addition of a cut fastball that, when paired with a slider that averages 89.1 mph, a four-seamer that sits at 97.5 and one of the fastest sinkers in the big leagues, has made him nearly unhittable.
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According to Statcast™, Treinen's cutter has accounted for just 7.3 percent of all his pitches this season, but he has produced a whiff rate of 43.6 percent with the pitch and opposing hitters are hitting just .111 off of it.
"The first time I faced him, he threw me the cutter for a ball. It went 97 and moved like a slider," Twins outfielder Jake Cave said. "It's just one of those things where you think you see a strike and swing, and it's either off your hands or off the end of the bat."
Treinen's sinker has always been an asset, and he threw it just as hard last season as he has this year. But he induced swings and misses with it at just a 16 percent rate in 2017 -- about half as frequently as he has this season. This season, hitters have been tasked with differentiating between a slider and cutter that look identical but are separated by 3.5 mph on average. The result has been a sharp increase in swing-and-miss rate on every one of his pitches, as well as an increase in the amount of weak contact he produces.
According to FanGraphs, Treinen leads the Majors when it comes to generating swings on pitches outside the zone (42.4 percent).
"I think with the righties, they're having a hard enough time just staying inside the ball against him," A's catcher Josh Phegley said. "But the cutter is the equalizer with the lefties to kind of stand them up. Usually, guys will just sit on the ball moving away. Even though it's hard, they're slapping at it. But now they've got the cutter and the four-seamer, and then he throws the slider on top of it. He's got too many weapons to protect against."
Treinen had tinkered with the cutter over the past few seasons, but didn't deploy it in a game until May this season. Tanner Roark worked with him on the pitch when the pair played together in Washington, and he adopted the grip he uses from A's reliever Chris Hatcher.
On May 27, he introduced the pitch against the D-backs and sat down the three batters he faced en route to his 12th save of the season. Since then, it has become a staple as he has racked up 88 strikeouts in 64 innings.

"To have my pitches that I have already with my sinker, four-seamer, slider and then adding the cutter to it, it just makes it probably a little tougher for a hitter to maybe track one moving in, one moving away, one moving in and one staying true, and then the slider," Treinen said. "I think the biggest thing is just trusting it and throwing it. For the most part, it's been a really good pitch for me."