Salas signed with Tampa Bay on July 8, 1998, as an amateur free agent, and made his Major League debut September 5, 2006.

Salas is notable for being converted from playing third base to pitching while in the Devil Rays' minor league system.

He was called up to the Triple-A Durham Bulls, with whom he went 1-1 with a 1.57 ERA and three saves in 27 games, striking out 33 batters in 282⁄3 innings.

Salas started the 2008 season on the restricted list due to problems obtaining a visa to come to the United States.

He missed spring training and did not arrive in the United States until April 17, 2008, several weeks after the 2008 MLB season started.