The Padres have designated lefty Eury De La Rosa for assignment, the club announced. San Diego selected the contract of corner infielder Brett Wallace in a corresponding move, necessitating a 40-man spot.
De La Rosa, 25, has pitched exclusively at Triple-A this year, working to a 4.03 ERA with 6.9 K/9 against 5.6 BB/9 over 22 1/3 frames. That represents a career-worst K:BB ratio in his professional career.
The southpaw spent time in the Diamondbacks bullpen over the past two seasons, putting up a 4.21 ERA in 51 1/3 total frames.