Duran discovered the signature pitch by accident during a bullpen session in 2018. This season, he’s thrown the pitch nearly 40% of the time and is holding opponents to a .221 average.

It was 30 minutes after Duran left the mound, and the Phillies readied to head home. Taijuan Walker sat at his locker and whistled Duran’s warmup song. Duran overheard him and smiled. A few minutes later, Alec Bohm whistled it as he left the clubhouse.

Those four pitches were all splitters as Duran finished out a Phillies comeback victory over the Tigers to take the series opener -- and regain first place in the National League East. In one of the most electrifying games of the year, Duran stole the show in his debut.