HOUSTON -- Carlos Zambrano brushed off the idea that his bad sixth inning on the mound Wednesday night was a result of being worked up after his home run in the top half of the frame.
Zambrano extended a franchise record with his 22nd career homer and ran his winning streak to 10 games, leading the Chicago Cubs to a 9-5 victory and a series win over the Houston Astros.
"It's not the first time that I hit a home run," he said. "It's number 22 for me. I've been excited 22 times."
Alfonso Soriano's home run off Wandy Rodriguez (0-2) capped a five-run first inning for the Cubs. Zambrano's homer -- his sixth against the Astros -- made it 6-0 in the sixth.
Zambrano (2-0) pitched five scoreless innings before the Astros jumped on him for five runs in the sixth. Carlos Lee, Brett Wallace and Bill Hall each drove in a run in the inning before Matt Downs hit a two-run homer to cut the deficit to 6-5.
"I just left some pitches in the middle and got crushed," he said. "That happens. The most important thing is we won the game today."
Chicago got three insurance runs on three hits off Wilton Lopez in the ninth.
Zambrano allowed seven hits and walked three in 5 2-3 innings to extend a winning streak that began last season. Marcos Mateo, Sean Marshall, Kerry Wood and Carlos Marmol combined for pitch 3 1-3 scoreless innings to close it out.
Manager Mike Quade was impressed with the work of his bullpen.
"There are a lot of reasons you win and lose ball games, so there were more reasons for us to win tonight because the club picked up Z," Quade said of Zambrano.
Rodriguez allowed five runs -- all in the first inning -- and nine hits in five innings.
"Wandy is so good and has done such a good job in this ballpark, even last year with throwing the ball," manager Brad Mills said. "To give up those two-out runs, his stuff is so good and he's done such a good job, it's a little bit of a shock."
Jeff Baker drove in two runs with a double to right field in the first inning. Soriano's two-out, three-run shot to the Crawford Boxes in left field made it 5-0.
"I made one mistake. I threw a lot of fastballs to Soriano," Rodriguez said. "I was throwing him inside. I needed to throw another pitch in that situation."
Starlin Castro singled with one out in the ninth before stealing second base and scoring on a double by Darwin Barney. Marlon Byrd reached and got to third base, and Barney scored on a throwing error by Lopez. A single by Aramis Ramirez scored Byrd and chased Lopez.
Rodriguez gave up three straight singles in the third inning to load the bases. His defense helped him out by turning a double play, and he struck out Tyler Colvin to end the inning.
Rodriguez was replaced by Fernando Abad, who gave up the homer to Zambrano, to start the sixth inning.
Lee's RBI single came after a walk by Michael Bourn and a single by Angel Sanchez to make it 6-1. Sanchez's single came on a soft grounder down the third base line that Ramirez watched roll outside the foul line before bouncing back fair just as Sanchez reached first base.
Wallace pulled Houston to 6-2 with his run-scoring single to center field. Hall drove in a run on a forceout to make it 6-3 before the homer by Downs. Wallace was thrown out on that play when he started toward second, but stopped before Barney dropped Hall's fly ball.
Downs homered before a walk by J.R. Towles chased Zambrano, who was replaced by Mateo.
Zambrano was already to the grass when Quade met him to get the ball as he left the game. Zambrano said he didn't realize Quade was so far from him when he took off and regretted walking that far from the mound.
He doesn't want this incident to make people think he's reverting to his problem-filled past that included being put on the suspended list last season after a dugout tirade.
"I went to the office after the game and I apologized to Mike," he said. "I didn't mean nothing. Believe me. The last thing that I want to do this year is disrespect the manager. I've never had a problem with a manager. It was my mistake. Next time I will wait more. In fact, I will wait for the reliever too so there's no problem."
Quade didn't feel like the placement of the handoff was a big deal.
"I didn't get there quick enough," Quade said with a laugh. "He was ready to go. I guess I should have been sprinting there. Hand me the ball, just don't drop the ball. I don't really care. I was hoping he wouldn't run me over. There's a certain amount of respect and stuff that goes with some of that but to me it's just give me the ball."
NOTES: Chicago OF Kosuke Fukudome was out of the lineup for the third straight day after straining his hamstring making a catch on Sunday. He is listed as day-to-day and the Cubs are optimistic he will be able to play by Friday and won't have to go on the disabled list. ... Houston 3B Chris Johnson was out of the lineup after being hit in the arm with a pitch a day before. Johnson said his arm was sore and swollen but that he should be able to play on Thursday. ... Several Astros, including Hunter Pence and Johnson along with manager Brad Mills, attended a lunch hosted by President George H.W. Bush and his wife Barbara on Wednesday. The former president chooses a handful of players and staff each season to attend the event.