Left-hander Robbie Ross was optioned to Round Rock to make room for Poreda.
The Rangers announced they signed first baseman Carlos Pena to a minor league contract and assigned him to Round Rock.
Poreda is 0-1 with a 3.09 ERA and two saves in 11 relief appearances for the Express. He has allowed one run in 9 2-3 innings over his last nine games.
This will be Poreda's third stint with Texas in 2014. He is 2-0 with a 3.29 ERA in 16 relief appearances in his first major league action since 2009.
Ross is 2-4 with a 5.61 ERA in 18 games, nine starts, with the Rangers this season. He opened the season in the rotation and was 1-4 with a 4.78 ERA before moving to the bullpen on May 20.
Pena, 36, made his major league debut with the Rangers in 2001. He has a career .233 average with 285 home runs and has played for eight teams.