"You always know how many options you have left," Diekman said. "It just got frustrating. I need to get out of my own way. I'm just in my way. I just harp on things too much. I just over-think [stuff]."
Diekman is 0-1 with a 6.75 ERA in 25 appearances. He has a 2.02 WHIP. He has walked 17 and struck out 29 in 21 1/3 innings. He posted a 3.80 ERA in 73 appearances last season, striking out 100 batters in 71 innings.
"He just needs to work on some things," Phillies manager Ryne Sandberg said.