Making his first start since April 20, Zambrano took the loss Friday night as the Houston Astros edged the Cubs, 3-1, for their fourth straight win. Lance Berkman drove in two runs and Michael Bourn had three hits to back Houston starter Felipe Paulino (1-7).
The Cubs now have been limited to one or two runs in six of their past seven games, including each of the past four. They're 3-23 when scoring three runs or fewer. Manager Lou Piniella has run out of things to say.
"I don't think I want to talk about our offense anymore -- I'm talked out," Piniella said. "We'll let them go out there and see what they can do."
Expect more lineup tweaks on Saturday. Piniella said rookie Tyler Colvin will start.
"I've been patient enough watching," Piniella said. "I'm going to let the kid [Colvin] play and see what he can do. We'll have him in the lineup."
Marlon Byrd led off Friday for the second time this season and had two hits, including an RBI double in the fifth.
"I can hit anywhere," Byrd said. "I go out there and try to play my game. I try to get hits, get on base, create havoc any way I can."
Koyie Hill also was expected to start behind the plate on Saturday. The Cubs aren't scoring and have to figure out a way to stop the other team on the bases. The Astros stole two on Friday.
"I know these guys are trying," Piniella said of his team, which dropped its fourth in a row for the third time this season. "I know they're trying. We see the same thing every day, day in and day out."
Zambrano (1-4), who switched to the bullpen after four starts, gave up three runs on six hits and three walks over 4 1/3 innings while striking out three. He was pulled after 84 pitches.
"I thought he threw the ball well," Piniella said. "He had a little trouble in the first inning with a lot of pitches and then he settled down. He did a fine job."
Thirty-four of Zambrano's total pitches came in the first. Bourn singled and scored one out later on Berkman's single. Berkman tried to stretch his hit and was caught in a 7-4-3-4-1 rundown. Carlos Lee doubled, and Zambrano walked the next two batters to load the bases before Pedro Feliz flew out. Of the total pitches that inning, 15 were for strikes, and Zambrano's fastball was around 90 mph.
"I felt good today," Zambrano said. "The most important thing was my fastball was good today, my sinker was good today. That's the important thing for me."
"He's been tough on us," Berkman said of Zambrano. "I don't care what his record is against the rest of the league, but against us he's the best pitcher alive. So he was tough again tonight. I don't know why he was in the bullpen, but I didn't notice any difference in the way he was throwing the ball. He looked really good."
Zambrano admitted to feeling a little rushed in the first inning, and pitching coach Larry Rothschild tried to get him to slow down. Zambrano was more efficient in the second, third and fourth innings.
"My last outing as a reliever was against St. Louis last Saturday," Zambrano said. "It's a little tough to be consistent with the strike zone [after a layoff] ... not even [Carlos] Silva, who is a strike machine, or Greg Maddux [could be consistent]. If Maddux went to the bullpen and tried to pitch in seven, eight days, I think he would have some location problems."
The Cubs have had problems finding their offense. They had a chance in the third when they loaded the bases with two outs, but Paulino got Aramis Ramirez to pop up to Berkman in foul territory.
Starlin Castro singled to lead off the fifth and advanced on Zambrano's sacrifice. Castro sprinted to third on the play and slid into catcher Humberto Quintero, who was covering. Castro's left shoulder slammed into Quintero's shin guard and the catcher fell on top of the shortstop. The rookie stayed in the game and scored on Byrd's double to tie it.
Castro was spiked in the right bicep on the play and had the marks on his arm to prove it.
"This hurts more," Castro said, pointing to his left shoulder.
"I landed on him," Quintero said. "I didn't want him to go home. Nobody got the ball.
"I did it on purpose," the catcher said. "The trainer came to me, and I said, 'I don't have [anything wrong].' I [landed on him] on purpose so the guy doesn't run to home plate."
"I was hoping they'd call interference and allow the runner to go home, but we got [Castro] in anyway," Piniella said.
Bourn singled with one out in the fifth for his third hit, stole second and scored on Jeff Keppinger's single. Zambrano then exited, and Tom Gorzelanny entered, his first relief appearance since trading places with Zambrano and first outing since May 26. Berkman doubled off the lefty's first pitch to drive in Keppinger and make it 3-1.
Being back in the rotation made Zambrano happy.
"It was pretty nice -- the first inning, when I saw the first batter, it was a different scenario," Zambrano said. "The most important thing was I felt good today."
"He looked good," Byrd said of Zambrano. "I'm sure he had some jitters, even though he is Big Z. Coming back, getting his feet wet again -- I'm excited to see his next start. You could see him starting to get his groove back again. Glad to have him back."
Now, if he could just get the offense going.
Carrie Muskat is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.