Escalona posted a 3.81 ERA at Double-A Reading, while Cartwright hit 10 homers between Class A and Double-A. (MiLB)

HOUSTON -- In an effort to add competition for the left-handed spot in the bullpen, the Astros acquired lefty Sergio Escalona from the Phillies on Monday in exchange for Minor League infielder Albert Cartwright. Escalona will be added to the 40-man roster.

Escalona, who was designated for assignment by the Phillies last week, will come to Major League Spring Training to compete for a spot in the bullpen. He was 4-8 with a 3.81 ERA and 10 saves in 50 games at Double-A Reading last year, holding lefties to a .188 average.

"Our guys have liked Sergio over the last couple of years," Astros general manager Ed Wade said. "They think particularly in a left-on-left situation he can really be helpful. He had a good winter ball season. He pitched in 24 games down there and was scored on in two games and un-scored upon in the others. To be able to add another young, left-handed arm, that made sense for us."

Escalona, who has allowed seven earned runs in 16 innings in 24 appearances for La Guaria in the Venezuelan Winter League, will compete with Fernando Abad, Gustavo Chacin and Wesley Wright for the left-handed specialist in the bullpen.

Escalona has Major League experience, posting a 1-0 record in 14 relief appearances for the Phillies in 2009 with a 4.61 ERA with five walks and 10 strikeouts. He earned his first Major League win in his Major League debut, hurling a scoreless inning in relief on May 17, 2009, at Washington.

Cartwright, 23, hit .294 in a combined 127 games at Class A Lancaster and Double-A Corpus Christi (35 games) with 10 home runs, 55 RBIs and 31 stolen bases, but the club has built some quality infield depth with Jiovanni Mier, Jonathan Villar, Delino DeShields Jr. and Jimmy Paredes among their top prospects.

"You build depth in your farm system for two purposes: one, to have those guys arrive in your uniform and play well for a long time and the other way is it serves you is to be able to build enough depth to trade surplus talent and fill a need, if you can, from within," Wade said. "We felt we do have some depth in the Minors at the middle infield spots, but we did not have that depth from left-handed bullpen help."