ARLINGTON, Texas -- With Colby Lewis being placed on the 15-day disabled list Tuesday, left-handed pitcher Martin Perez has been called up from Triple-A Round Rock to fill Lewis' spot on the roster.

The Venezuela native was signed by the Texas Rangers as a non-drafted free agent on July 2, 2007. He has worked his way up through the system and now finds himself with an opportunity to show the big league club what he can do.

"I've been working hard, and it's finally paying off for me," Perez said. "I was called up here to help the team as much as I can."

And that's what he will try to do. General manager Jon Daniels said Perez has earned the chance.

"He's throwing a lot of strikes, really attacking the zone," Daniels said. "He's being very aggressive. Where we feel he is right now, if the can continue on that same path, we feel he's got a chance to help us."

Perez's last two starts really caught the Rangers' eyes. On June 15, Perez gave up one hit and five walks with four strikeouts in seven shutout innings of work. He followed that outing with a complete game June 21, giving up two runs on three hits and two walks to go along with four strikeouts.

"I've been working on a lot of my pitches in the bullpen," Perez said. "That's really been helping me a lot."

Perez will be available in the bullpen Tuesday night. He is in contention with Justin Grimm, who has made two starts since being called up from Double-A Frisco, to start Saturday against the Oakland Athletics.