Cam Schlittler just got some huge praise from David Ortiz ... who shoveled the "ace" label on the Yankees rookie following his incredible game on Thursday night.
Just hours after the New York hurler went eight innings of shutout ball in a do-or-die win over the Red Sox, Ortiz fired off compliment after compliment after compliment on the right-hander.
Big Papi -- who had just gotten off a flight at LAX -- told us he's already seen enough from the flamethrower to dub him a front-of-the-rotation guy.
"He's got it, bro," Ortiz said.