Lopez gave up three runs on three hits and two walks over three innings in Sunday's Grapefruit League game against the Cardinals. He struck out two.
The 24-year-old took the bump 21 times for the Marlins last season but stumbled to a 5.09 ERA and 95:27 K:BB through 111.1 innings, and Lopez hasn't shown anything in the way of improvement this spring, posting a 5.87 ERA, 1.70 WHIP and 5:5 K:BB through 7.2 frames. He's still ticketed to fill a mid-rotation role for the club to begin the season, but he could be on a very short leash if he can't take his performance to another level.