In his Japan career, Koji Uehara mostly got by with a fastball and forkball, while also mixing in a cutter and shuuto. For the start his Orioles career, the control specialist is shoring up his repertoire with a couple new pitches. The first is a changeup. "It's got good movement. I'm going to use it in games," said Uehara of his change. Later adding, "even if I can't miss bats with it, it'll be good if I can upset the batter's timing. I'm planning to use it".
More noteworthy, however, is Uehara's new spike-curvey pitch of his own creation. Uehara's never really thrown a curveball much - 1-2 times per game in Japan, though I don't remember ever seeing him throw one. He's calling his new creation a "one finger curve", which he grips with his middle finger only. You can clearly see the grip in this Nikkan Sports photo of him working on this pitch. Said Uehara of the grip: "if I apply my index finger, I can't use my middle finger and the ball doesn't break. So I arrived at this grip." The idea is to throw with a speed and break in between a traditional curve and a slider. Uehara also committed, "my form is still loose, but I want to use the pitch".
Commenting on the MLB ball, Uehara said: "the Japanese ball is less slippery and easier throw. But the breaking pitches really move".