The Nationals added a pair of pitchers to their farm system on Sunday, acquiring right-hander Omar Poveda from the White Sox in exchange for cash considerations and signing left-hander Aaron Laffey to a Minor League deal.

Poveda, 26, spent last season in the Braves' system, pitching in 27 games and making 25 starts for Triple-A Gwinnett. The Venezuela native posted a 3.62 ERA in 164 innings, striking out 133 and walking 59. He has spent eight seasons in pro ball since signing with the Rangers in 2004 and had joined the White Sox as a Minor League free agent in December.

Laffey had signed with the Orioles in January and was released on March 24 after pitching only in Minor League camp during Spring Training.

The 28-year-old has spent parts of the last seven seasons in the Majors with the Indians, Mariners, Yankees, Blue Jays and Mets, going 25-29 with a 4.45 ERA in 153 games, including 68 starts. He appeared briefly for the Mets and Toronto last season, starting three of his five games and posting a 7.11 ERA. He also had a 6.34 ERA in 110 2/3 innings for two Triple-A Pacific Coast League affiliates.