To make room for Saunders on the major league roster, INF-OF Alex Castellanos has been designated for assignment.
Saunders, 32, was 11-16 with a 5.26 ERA in 32 starts for Seattle in 2013. He tied for the Mariners team lead in complete games (2), ranked second on the staff in starts and was third in wins, innings (183.0), and strikeouts (107). The lefthander was signed by Seattle on February 13, 2013 and became a free agent following the season when the Mariners declined his 2014 option.
Saunders has a career record of 89-81 with a 4.30 ERA in 221 games, all starts, with the Angels (2005-10), Diamondbacks (2010-12), Orioles (2012), and Mariners. He posted a 33-14 record for Los Angeles in 2008-09, winning a career best 17 games for the A.L. West champs in 2008. Traded from Arizona to Baltimore on August 26, 2012, he went 3-3 in seven regular season starts with the Orioles the rest of year, then allowed one run in 5.2 innings to defeat Texas in the A.L. Wild Card Game in Arlington.
Castellanos was claimed on waivers from Boston on December 23, 2013 and had appeared in five games this spring, going 3-for-9. Texas has ten days to trade, release, or outright Castellanos to the minor leagues.