Oliver Perez is making progress toward his return to the Pirates' pitching rotation next weekend.

Perez, who missed his start Wednesday because of stiffness in his left shoulder, is scheduled to throw in the bullpen again today. That follows his bullpen session Friday that went well enough that the Pirates have tentatively scheduled him to start against Colorado.

Manager Lloyd McClendon said yesterday Perez will not start either game against the Chicago Cubs Tuesday and Wednesday.

The Pirates begin a trip to St. Louis and Cincinnati May 23.

"I would like to have him pitching before we go on the road," McClendon said. "Just when, we don't know."

If Perez were to start Saturday night against the Rockies at PNC Park, he'd be in line to start again in Cincinnati May 26. Perez has a great track record against the Reds.

"There are a lot of things that come into play," McClendon said. "The health of the pitcher is the No. 1 concern. The rotation is another concern."

Perez apparently is healthy and won't go on the disabled list. The Pirates think his difficulties are mechanical in nature. Pitching coach Spin Williams has worked with Perez on that and saw improvement Friday.

Mackanin king for a day
McClendon will miss the game today, so he can attend the graduation of his daughter, Schenell, from Valparaiso University in Indiana. Bench coach Pete Mackanin will manage the Pirates today. Infield instructor Alvaro Espinoza will serve as Mackanin's bench coach.

The Pirates' lineup for the game today was made out by McClendon before the game last night.

"But [Mackanin] has all the flexibility," McClendon said. "You talk about some stuff, but he still has to have his feel for the game and his gut as to how things are going and how the starting pitcher's pitching, how we're hitting."

Mackanin, who has managed in the minors and winter ball, has managed the Pirates before when McClendon has been ejected or has served suspensions.

Does he find it interesting? Does he look forward to it?

"Actually, I don't like managing when Mac's not here," Mackanin said. "When you have your own team, you have certain ideas on how you like to do things, and I have to couple that with what Mac likes to do.

"I wish he just wouldn't leave," he said. "I wish he would just stay here."

Still in the learning process
McClendon mentioned after the game Friday, which Kip Wells started, that the game plan wasn't followed at times.

"The fact is, we have young players who are going to make mistakes from time to time," McClendon said. "That's part of the growing pains, and, as they continue to learn -- the more they go out there -- they won't make those mistakes. I was talking about how we attack certain hitters. And, when the game's on the line, you want to stick to that scouting report as to how we choose to attack guys. So ... you make a mistake, live and learn and get better."

Longtime Pirate employee dies
Charles R. Muse, an employee of the Pirates in a variety of positions for 52 years, died May 5 in Sun City Center, Fla. Muse, 87, also was instrumental in the development of the first batting helmet.