CHICAGO -- Jake Peavy will be back in Chicago this weekend, set to throw his third side session off a mound, following Wednesday's successful effort in San Diego.

If all goes well, the right-hander acquired by the White Sox from the Padres just seconds before last Friday's non-waiver Trade Deadline could begin a Minor League rehab stint on Aug. 13 to test the strained right tendon in his right ankle. White Sox pitching coach Don Cooper didn't have a destination for Peavy, though both Triple-A Charlotte and Rookie-league Bristol will be home on that Thursday.

"Not sure. We aren't that far ahead yet," said Cooper of the potential injury rehab debut for Peavy. "We just have to see how Saturday goes. The scheduling of where and what we have to do, we'll look at our Minor League teams and look at where they are at. We haven't gotten to that one.

"We have some dates tentatively in mind, but we are going to sit down with him and map this out. We need [Peavy's] input. It's something we aren't going to dictate, 'This is exactly what we are doing.' We are going to come up with a plan, and with any plan, you better be flexible, or it's not as good as you think it was in the first place."

According to Cooper, Wednesday's side session "went very well," and Peavy "turned up the intensity more."

Ozzie Guillen talked with Peavy after Wednesday's bullpen, and the White Sox manager liked what he heard.

"He's doing very well, and excited about the ballclub," Guillen said. "I didn't know he would be that excited. I'm not the type of guy who calls anybody. [White Sox general manager] Kenny [Williams] sent a message and said Peavy threw very well. I want to talk to him and see how he feels. He's got to get his arm back in shape.

"But he's anxious to pitch on the big league level. I don't know how many outings he's going to have in the Minor Leagues. But I think this guy, the way he is and the way he's throwing, I don't know the guy at all, I talked to him yesterday, and he sounded very, very positive. I bet you he'll be here very soon."

Cooper said Peavy would need at least three rehab starts, which would leave him ready to open the three-game set at Yankee Stadium on Aug. 28 if the plan works out at three.

"You know, he's going to tell us more and more as we go," Cooper said. "He's going to give us a lot of the answers, how he's feeling and how he's throwing."

In the interim, the White Sox once again were without closer Bobby Jenks on Thursday following a procedure to break up his remaining kidney stone on Wednesday. Guillen, who has previously gone through the pain of kidney stones, didn't think Jenks would be available this weekend.

"Hopefully, he's coming back the way the doctor says he is," said Guillen of Jenks. "I doubt he's going to be ready by the end of this weekend."

There was no official word yet on Saturday's starter, filling the void at No. 5 until Peavy is ready. It looks as if Carlos Torres will get the nod and be called up from Charlotte. Torres allowed three runs on six hits over six innings in a spot start on July 23 against Tampa Bay.