By GEORGE A. KING III

May 29, 2008

BALTIMORE - When Andy Pettitte took the Camden Yards' mound last night, he was aware the Yankees wanted to give Joba Chamberlain the opportunity to throw 50 to 55 pitches in order to get him ready for the rotation.

Nevertheless, if they planned on needing Chamberlain to throw four innings to reach that goal, they were in for a battle.

"They would have been a fight on the mound," Pettitte (5-5) said after he helped defeat the Orioles, 4-2, with 62/3 innings in which he allowed two runs and eight hits.

When manager Joe Girardi replaced Pettitte with Chamberlain in the seventh with two outs, the bases empty, the Yankees ahead by a run and Melvin Mora due up, Pettitte didn't approve of the strategy. Even if Mora had a single, homer and walk off Pettitte.

"I wasn't OK with it. I still felt strong," Pettitte said after 96 pitches. "It's the same old stuff, Joe is the manager. I am never happy, but (Chamberlain) throws 98 mph."

Chamberlain preserved the lead and Mariano Rivera posted his 13th save in as many chances by getting the final three outs.

The biggest out Pettitte recorded was in the fifth, when he picked Brian Roberts off second after Roberts doubled with one out and the Yankees ahead, 3-2.

"They got a couple of more hits and that could have changed the complexion of the game," said Girardi, who watched Pettitte walk Mora and Nick Markakis double after Roberts was picked off.

Pettitte rebounded to get Kevin Millar on a stress-free fly to center.