The 24-year-old De La Rosa was designated for assignment last week to clear room for Allen Webster and Rubby De La Rosa, who were acquired in the Wade Miley trade with Boston. The A’s have acquired a lefty relief option that pitched to a strong 2.95 ERA with 7.9 K/9, 3.4 BB/9 and a 43.1 percent ground-ball rate in 36 2/3 innings. However, the now-former Diamondback also turned in a reverse platoon split last year in Arizona, yielding a .309/.377/.418 batting line in a small sample of 61 plate appearances versus left-handed hitters.
Rodriguez, 30, appeared in seven games for Oakland in 2014 and allowed just one run in nine innings with four strikeouts and two walks. However, he’s yet to establish a track record of success in the Majors, having seen inconsistent playing time in the bigs dating back to 2009 and compiling a 4.62 ERA. He does throw relatively hard (career 93.3 mph average fastball) and did excellent work at Triple-A in 2014 (1.97 ERA, 10.4 K/9, 3.2 BB/9 in 45 2/3 innings), so another club could view him as a depth piece.