Roy Halladay could not hide his smile.

He learned Thursday the Phillies had acquired Houston Astros ace Roy Oswalt for left-hander J.A. Happ, outfield prospect Anthony Gose and infield prospect Jonathan Villar. The Phillies also received $11 million from Houston to pay a portion of the roughly $23 million remaining on Oswalt's contract.

Oswalt will make his Phillies debut Friday night against the Washington Nationals at Nationals Park.

"Coming from a team that wasn't able to do things like this, getting to this point in the season and getting probably one of the best pitchers out there, that says a lot," Halladay said in the Phillies' dugout at Citizens Bank Park. "The team is dedicated to winning. They're not going to rest."