Jun 29, 2009 4:21 PM EST

Blue Jays left-hander Ricky Romero has been frustrating hitters with an off-speed pitch this season.

Hitters have asked Romero if he is throwing a splitter or a screwball, but ESPN's Buster Olney says that he throws a changeup with a classic circle grip.

Romero's pitch doesn't move like a traditional changeup.

"It's a tremendous finishing pitch," one general manager said this weekend.

The pitch tends to move away from right-handed hitters, and reminds many of Fernando Valenzuela's screwball.

Via ESPN