OAKLAND -- Just days after adding right-handed reliever Sandy Rosario from the Boston Red Sox, the Oakland Athletics have added another right-handed reliever in a trade with the Pittsburgh Pirates. Oakland acquired Chris Resop from Pittsburgh in exchange for minor league pitcher Zach Thornton. Resop, 30, has seven years of big league experience. He has a career 4.51 ERA in 225 13 innings. He appeared in 61 games for the Pirates last season with a 3.91 ERA, 46 strikeouts and 24 walks in a career-high 73 23 innings. Resop has a low 90s fastball, a curveball, and mixes in a cutter and a change-up. He'll likely be a suitable replacement for reliever Jim Miller who was claimed on waivers by the New York Yankees after being designated for assignment by Oakland on November 20. Thornton, 24, was drafted in the 24th round by the A's in the 2010 MLB June Amateur Draft. He spent the 2012 season in Single-A Stockton where he had a 4.53 ERA in 48 games.According to the A's, a move to clear space for Resop is forthcoming later tonight. Oakland has until midnight Eastern time to tender contracts to their remaining five arbitration eligible players. If one of those players is non-tendered, it will clear space on the 40-man roster for Resop. The five players that are still arbitration eligible are Adam Rosales, Brandon Moss, George Kottaras, Seth Smith and Jerry Blevins.