Maxwell will give the Astros a right-handed outfield option off the bench, something they've been without since trading Jason Bourgeois. The Astros currently have four outfielders on their roster, though infielders Brian Bixler and Matt Downs can play the outfield.
Maxwell, 28, spent his entire 2011 season at Triple-A Scranton/Wilkes-Barre in the Yankees system, hitting .260 with 16 home runs and 35 RBIs. He appeared in 27 games for the Yankees this spring, hitting .310 with 11 RBIs before being designated for assignment on Wednesday.
"Just looking at what he did last year in limited playing time in Triple-A -- 16 homers in 48 games -- he's got some speed and can play the outfield, all three positions," general manager Jeff Luhnow said. "We had our scouts look at him this spring and we suspected he might be available, and when he became available it was a pretty easy decision for us."
The only Major League experience for Maxwell has come with the Washington Nationals, for whom he appeared in 122 games (2007, 2009-10). He's played all three outfield positions in his Major League career, including 57 games in center field.
Luhnow said the Astros have to take advantage of having the first crack at waiver claims, based on finishing with the worst record in the league last year.
"It's nice when you claim someone, you know you're going to get him in this position," he said. "Hopefully, we're not in it for too long, but for now it's a nice position to be in. He'll be here tomorrow and we'll figure out where to go from there.
"When an asset like that becomes available, there's really no downside to bringing him in. We're going to take advantage of it. This won't be the last time you see that."