"I seem to have more of a problem with getting up multiple times, where I get up, for example, and come in and pitch the eighth, and then have to sit for 15 minutes, and then come back and pitch in the ninth," Gregg said. "For some reason, that is not meshing very well with my knee right now. But if I can get up, get hot, get in the game, my stuff has been on."
Manager Lou Piniella revealed the knee issue in Milwaukee, saying Gregg's leg tends to tighten up. It's not a problem with the knee itself, but the muscles around it.
The plan now is to limit Gregg to one inning, not multiple innings.
"I've never had knee surgery before, and I don't remember when a pitcher had this kind of knee surgery," Gregg said of the procedure, in which doctors had to "butterfly" his knee and take a part of it out. "It's something that's trial and error, and we're working things out here this first week."
So far, he has one save, April 6 in the season opener against Houston, and one blown save from last Friday in Milwaukee. Gregg has given up four earned runs over four innings, but on Monday in the home opener against Colorado, he struck out the side in Chicago's 4-0 win.
The frigid weather Monday wasn't conducive to pitchers, hitters or fans. No one wants to deal with a wind-chill factor on Opening Day.
"I don't think anybody really wants to hit in those conditions," Gregg said. "It's hard to throw a baseball in those conditions, too. It's cold, it's wet, you don't have good footing underneath you. There's pros and cons to both sides."
Gregg got mixed feedback from the fans, as well. As he was warming up for the first time in front of the home crowd, some of the folks sitting near the bullpen at Wrigley Field shared their feelings. Apparently, many were still peeved about last Friday's game at Miller Park which the Brewers won, 4-3, on a walk-off fielder's choice by Ryan Braun.
"They were talking -- some people were booing me, some people were, 'Hey, don't worry about it,'" Gregg said. "I don't care [about the negative reaction]. I like talking to people. I have no problem. There's nothing to it.
"It's fun to go out there; it's fun to pitch," he said. "I really enjoy winning, so that was the good part. I'm just glad to get out there and pitch and get my bearings on what I'm doing."
It's not just finding his way around the Cubs' clubhouse that will take some getting used to, but, more importantly, what Gregg's knee can and can't handle.
"At the start of Spring Training, it was a learning process to how my knee was going to react to being on the mound for the first time," he said. "Spring Training games, once they started, it was a stepping stone. How's it going to react to these kind of games?
"OK, then the regular season starts -- how's it going to react to these kind of games? The intensity level is completely different [in the regular season]. And the fact that I've pitched every day. I've been up every day except for one so far. How am I going to maintain a healthy knee in these conditions?"
Gregg, Piniella, pitching coach Larry Rothschild and athletic trainer Mark O'Neal met to determine the best conditions for Gregg coming off the surgery. Gregg expects his velocity to improve as his knee gets stronger and the season progresses. A 5-2 record helps ease some of the aches and pains he's dealing with.
"I've talked to the doctor who did my surgery and talked to the team doctors," Gregg said. "They said this is to be expected. I've hit every step along the way, and it's to be expected to have the soreness and have all these things. They say I'm doing pretty good, as far as the amount of soreness I have. It's working in my favor."
That's what the Cubs want to hear.