Los Angeles Angels star Shohei Ohtani began the 2023 season with a twist: calling his own pitches through a PitchCom device hidden underneath his jersey near his left shoulder.

Ohtani's decision to call his own game is directly related to the pitch clock.

"Shohei's got so many pitches he can throw," Angels manager Phil Nevin said before Thursday night's season opener against the A's in Oakland, California. "So for him to go through 'em and shake and shake and shake -- time's running out because that thing doesn't say it quick enough sometimes."

Other pitchers, including Angels reliever Ryan Tepera, are using the device to call their own pitches but placing it on their non-throwing wrist or forearm, where they can easily see the numbers as they type them in. Ohtani's use of PitchCom is different; he had to memorize the keypad in order to use it without seeing the numbers on the pad.

Major League Baseball approved the use of PitchCom for pitchers last Friday; instead of the catcher keying in the pitch selection and the pitcher hearing it through a speaker in his cap, the sequence is reversed.

"They're pushing buttons, they're making eye contact," Nevin said of Ohtani and rookie catcher Logan O'Hoppe. "It's a little different dynamic than we've seen in the past, obviously, but however they get there is fine with me."

Ohtani's fortunes on the mound last season changed drastically after he made the switch to PitchCom. In April and May, he had an ERA of 3.45. In his first four starts after adopting PitchCom, he threw 26 ⅔ innings with an ERA of 0.34, with 36 strikeouts and six walks. He finished the season with a 2.33 ERA, fourth in the American League.