PHOENIX -- It was after throwing seven shutout innings on Saturday against the Dodgers when pitcher Jake Peavy poked his head into manager Bud Black's office and floated the idea of pitching on three days' rest.

So much for reveling in the moment and enjoying his 16th victory of the season, against a National League West Division rival, at that.

Peavy was already looking ahead to the three-game series against the Diamondbacks, a series he wasn't scheduled to throw in.

Not initially, at least.

"I want to compete in this series," Peavy said. "I'm healthy enough to do this. I want to go out and compete to win against a team that's right there with us in the standings and have been the last couple of months."

So it will be Peavy who will get the start in the series finale Wednesday against Arizona at Chase Field, as the right-hander will start on three-days' rest for the first time since the 2004 season when he did so, oddly enough, against the Diamondbacks.

"We thought his last start ... he was throwing very efficiently, free and easy, came out of that one great," Black said. "After the game, he came in and said, 'I feel good, if you guys want to talk about three days' rest, fine'. We had been thinking about it."

The Padres first hinted at starting Peavy before Monday's 10-2 victory over Arizona. The only other potential candidates were rookie Jack Cassel, Wil Ledezma and Clay Hensley, who was recalled on Tuesday from Triple-A Portland.

There were several factors that made Peavy's situation much more palatable. He threw only 99 pitches in Saturday's victory over the Dodgers at PETCO Park, seven mostly drama-free innings.

That the Padres have an off-day on Thursday and again on Monday, giving Peavy an extra day to recover from Wednesday's start. He'll likely start the first game of a three-game set in Los Angeles on Tuesday.

"Jake feels rested, his arm feels good. The way he's throwing now with the two off-days coming, it's a good opportunity for us to pitch Jake against the Diamondbacks and also lead off the series against the Dodgers when he'll have an extra days' rest to bounce back from this one," Black said.

Peavy, who on Tuesday was named the NL Pitcher of the Month for August, impressed Black with the way he was proactive about making one more start this season against a team he's 3-0 with a 1.71 ERA against in four starts in 2007.

"I think the combination of him feeling good and I wouldn't say his insistence ... but he was amped," Black said. "It was great.

"I think the players knew that Jake wanted to do this so I think that is a situation where the guys respect that and appreciate that he's doing everything he can to help the team win."

Peavy didn't seem to think starting on three-days' rest was that big of a deal, even if he has only done it once previously.

"I feel good and I don't think it's that big of a deal," he said. "The only difference is I'm pitching one day sooner than I would have," Peavy said. "I'm not trying to send a message to anyone on the team, other than I'm trying to win a game for us this series."

So long, Pete: The Padres officially parted ways with catcher Pete Laforest prior to Tuesday's game, though they weren't entirely happy about it.

Laforest was designated for assignment last week to create a vacancy on the Padres' 40-man roster. The Padres hoped Laforest -- who served two different tours with the Padres this season -- would have cleared waivers so that he could rejoin the team this week.

But Laforest, who hit .360 with a home run and three RBIs in 10 games, was claimed by the Philadelphia Phillies, who needed a left-handed bat off the bench.

"We're going to miss Pete ... he was with us in Spring Training," Black said. "He picked us up when [Josh] Bard got hurt and did a nice job filling in. He was here [Arizona] thinking he'd rejoin us."

Towers indicated the Padres will recall a catcher from their Minor League farm system on Wednesday so that they have a third catcher on the roster.

Friar notes: Hensley was officially recalled from Triple-A Portland on Tuesday. He, along with Jack Cassel and newly-acquired Brett Tomko, are candidates for the team's fifth-starter spot, which won't be needed until Sept. 15. ... Chase Headley, who won't be recalled this month, had four hits for Double-A San Antonio's regular-season finale to raise his average to .330. The Missions begin the Texas League playoffs on Wednesday. The only other Padres farm team that qualified for the playoffs is Class A Lake Elsinore. The Storm opened the California League playoffs on Wednesday.

On deck: The Padres conclude their three-game series against the Diamondbacks at 6:40 p.m. as Peavy (16-5, 2.10) gets the start for San Diego on three-days rest. Arizona will counter with Livan Hernandez (9-9, 4.67), who, oddly enough, pitched on three-days rest last week.