CHICAGO -- The Pirates removed James McDonald, one of the National League's better starters in the first half of the season, from the starting rotation Sunday because of the sharp decline in his second-half production.
Rookie right-hander Kyle McPherson will take McDonald's place Wednesday against the Milwaukee Brewers.
"As the games count down, we've got to look to give ourselves the best shot that we can of winning the game," Pirates manager Clint Hurdle said.
McDonald has a 7.08 ERA in the second half of the season after finishing the first half with a 2.37 ERA. He has walked more batters in 61 second-half innings than he did in 110 first-half innings and has allowed almost twice as many home runs as he did in the first half.
"The realization that something's been taken away, maybe that can help," Hurdle said. "He wants to do well. I don't think you could ever misconstrue that."
McDonald previously pitched out of the bullpen in 2010 while in the Los Angeles Dodgers organization. He pitched almost exclusively out of the bullpen in 2009, his first season with extended major league service time.
"He's so far removed from that, I do think this will be somewhat foreign to him," Hurdle said. "It's going to be up to him what he provides, and his buy-in. There's still a lot at stake for everybody here. He has a role to play on this club. I anticipate him being very good with it from that end."
McDonald currently has the same number of innings pitched, 171, as he finished with last season. Hurdle said he didn't believe fatigue affected McDonald.
"The execution was challenging, to say the least," Hurdle said. "The velocity, sometimes one start it would be higher than the next. It wasn't like it was slowly, gradually working down, which would lead you to believe maybe there was some fatigue involved."
McPherson, 24, a 14th-round pick in 2007 and the Pirates' minor league pitcher of the year in 2011, has allowed two runs in 112/3 innings of relief with the Pirates this season. He had a 3.22 ERA in 12 starts split between Class AA Altoona and Class AAA Indianapolis after shoulder inflammation kept him out for the early portion of the season. He struck out 63 and walked only nine in 67 minor league innings this year.
"We got to a point in time where we felt Kyle gave us a better chance to win that game against Milwaukee," general manager Neal Huntington said.
Hurdle spoke with Jeff Karstens, another starter currently in the bullpen, Sunday and expressed hope in adding Karstens to the rotation if the pitcher can get healthy.
Karstens has dealt with right hip soreness on and off in the second half of the season. He left his previous start Aug. 31 after recording only one out because of pain in his hip.
"The next test is the game adrenaline," Hurdle said. "We've done this dance with him before. We prepare the best we can. We went in that game, [and] 15 pitches into the game, we weren't in a good place. We do want to get him back into a game facing hitters and see how he fares."
Bill Brink: email@example.com and on Twitter@BrinkPG.