BOSTON -- The Boston Red Sox have fired pitching coach Bob McClure, the team said Monday. Assistant pitching coach Randy Niemann will serve in that role for the remainder of the season.

General manager Ben Cherington said the decision to relieve McClure of his duties for the remainder of the season was solely "performance based" and had nothing to do with McClure's relationship with manager Bobby Valentine, which reportedly was strained.

"This is a performance-based decision," Cherington said. "As I said (in New York on Sunday), and I think Bobby has said, there's been a really good effort on the part of the staff to work together and iron out any communication issues that existed previously and this decision had nothing to do with that. We simply felt we needed to make a change to put our pitchers in the best position to do what they needed to do in the next six weeks.

"We feel the next six weeks are important no matter what our record is. Anything we need to accomplish in the next six weeks is to provide and create a foundation going into the offseason. We felt this change was needed to have the best chance to do that."

The Red Sox rank 11th in the American League in ERA at 4.31; their starters' ERA is a combined 4.82.

Niemann will be the Red Sox's fourth pitching coach since 2010, following John Farrell, Curt Young and McClure.

The Red Sox originally hired McClure as a special assistant for the organization last November, before Valentine was named manager, but a month later McClure was named pitching coach. He had spent the previous six seasons as the pitching coach for the Kansas City Royals.

Cherington said McClure would not stay in the Red Sox organization.

"We've relieved him from his duties and he's no longer working for the Red Sox," Cherington said. "We have great respect for Bob, he's a quality guy and a good coach. It just didn't work out as we had hoped and when it doesn't work out, we have to look at ourselves first and ask what, if anything, can we do to make it work better, so we'll do that. The fact that it wasn't working out, we felt like we needed to make a change and the right thing to do was to get a fresh start, and Bob will get a fresh start and we expect him to get an opportunity somewhere else."

Niemann, also in his first year with the Red Sox, was one of two hires made by Valentine for his coaching staff (third-base coach Jerry Royster is the other). Niemann also served under Valentine while he was manager of the New York Mets.

"Randy's got a lot of experience," Cherington said. "He knows our guys well. He's been involved with our pitching staff pretty intimately since spring training and there won't be a learning curve, that's for sure. He's done most jobs in the game, and obviously was a major league pitcher himself, and has a long coaching career. He's got a lot of experience and we feel like he can be part of the solution to making sure we get a lot of good work done from the pitchers for the rest of the season."

When asked if there would be any more changes to the Red Sox staff coming before the end of the season, Cherington said, "No."