It was a brief stint with the Red Sox for Sanchez, who came on board and started last Thursday's game at Fenway while starting shortstop Marco Scutaro recovered from a cortisone shot in his left elbow.
"We'll get back to having a normal bullpen and let Sanchez go back and play," said Red Sox manager Terry Francona. "Because of some of the length our starters gave us the last four or five days, we felt we could go through a National League city [with 11 pitchers] and potentially it would help us. Now we're back in American League baseball. It will be nice to have the arm."
Atchison posted a 6.10 ERA in seven outings in his first stint with the Sox. In eight games for Pawtucket, Atchison was 1-0 with a 1.64 ERA.
"I was able to maybe work on little things, maybe get my curveball back over for strikes," Atchison said. "It was just kind of getting everything locked in and trying to feel like I felt in the spring, to be honest. I feel like I was able to accomplish that. Hopefully, I can carry that over up here."
Francona said he thinks that Atchison is someone he can depend on.
"I think it's a guy that we probably liked more than people realize anyway. He's been throwing in a lot of different situations," Francona said. "He's a strike thrower. He's got that cutter for lefties. I think we're actually glad we could get him back. We like him. I think we think he can help us."