On Thursday, the problem was a cracked molar.
"I've been out to the mound many times to check pitchers' injuries," Cubs manager Lou Piniella said of a visit in the fifth inning, "but never for a cracked molar. We needed a dentist."
Zambrano spit out the tooth and stayed in the game. He didn't need much help as he almost single-handedly beat the Cincinnati Reds, 3-2. The right-hander hit his fourth home run, and gave up one run over seven innings for the win, ending his three-game winless streak. On Friday, he'll get his tooth fixed.
It was just another "Cubby occurrence," a phenomenon Piniella has discovered in his nearly two years in Chicago.
"That was a first for me and a first for the umpires," Piniella said.
"I think I ate too much gum, and the gum has a lot of sugar," Zambrano said. "I keep telling my daughter not to eat a lot of gum and I'm not a good example. I think my daughter today will be all over me at the house. I accept it."
The Cubs had not been worried about Zambrano's oral hygiene lately, just his pitching mechanics. He was winless in three August starts, and had been rushing his delivery. Against the Reds, he was back in sync, and the Cubs were able to win their seventh straight series.
"I think I'm trying to do too much and I'm trying to be too perfect," Zambrano said about getting out of whack. "Sometimes being too perfect, the ball doesn't come out of my hand the way I want. Any time I'm on the mound, I just want to take my time and let the ball come out of my hands and make a good pitch and whatever happens, happens."
What happened in the third was his 16th career homer, which extended his hitting streak to seven games.
"I believe you could put him in the lineup every day and get production out of him," said Mark DeRosa, who also homered, hitting a solo shot in the second. "He's that type of offensive threat. I hope one day he can go in the 'Home Run Derby' because, if people had a chance to see his early [batting practice], he hits the ball further than anyone on this team."
Zambrano (13-5) entered the game 0-for-August. He walked Reds leadoff man Chris Dickerson on four pitches, and Dickerson advanced to third with one out. But Zambrano got out of the inning, and the only run off him came when Jay Bruce connected on the first pitch with one out in the sixth for his 13th homer.
Big Z did have several animated conversations with himself, especially in the first.
"He's had conversations before," Piniella said. "I'm excluded from those conversations."
"You've got to let him go, let him do his thing," Cubs catcher Henry Blanco said. "He'll figure out what he's going to do."
Want to know what Zambrano says during these little chats?
"I was saying to myself that it's not that hard," Zambrano said. "I told myself, 'It's not hard to throw strikes, c'mon, let's go. You have a good sinker today, just throw it in the middle and the ball will run toward the hands of a right-handed hitter.'
"I'm tired of walking [guys] -- I don't like that," Zambrano said. "I would rather people go out there and hit a home run than walk somebody. I hate walks. Walking somebody, I hate that. I know that I can get somebody out and I walked that guy and it [ticks] me off."
Josh Fogg (2-6) knows the feeling. Alfonso Soriano walked to lead off for the Cubs, and eventually scored when Derrek Lee grounded into his National League-leading 24th double play. DeRosa made it 2-0 with his 15th homer, notching his 73rd RBI, one shy of his personal best. Zambrano then connected in the third to go ahead, 3-0.
He's pretty confident at the plate.
"I'm 6-5, 200-some pounds," Zambrano said. "I was able today to connect on a pitch in the strike zone and thank god I hit it out of the ballpark. I feel good at the plate right now. Just keep going."
"He's strong," Blanco said. "You leave a pitch there and he'll make you pay."
The only other glitch for the Cubs came in the Reds eighth when Joey Votto launched his 15th homer off Carlos Marmol, the first runs off the right-hander in 16 innings since the All-Star break. Marmol did not report any problems with his teeth after the game.
"[Zambrano] is a special player," DeRosa said. "The ability to go out and pitch seven innings of one-run ball and hit a ball 420 feet, you don't see that a lot."
No, you don't. Must be a Cubby thing.
Carrie Muskat is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.