Milton Bradley hit a solo homer and scored on Aramis Ramirez's RBI single to back Wells (10-7), who gave up seven hits over 6 2/3 innings. Wells is the sixth Cubs rookie to reach double-digit wins since 1970, joining Wood, Mike Harkey, Geremi Gonzalez, Burt Hooton and Rick Reuschel.
"He's had a really nice first year," Piniella said of Wells, a converted catcher. "He needs to finish up strong. We've been impressed with him. He's a serious-minded kid, who goes about his business and competes really well."
If told this spring that he would lead the Cubs in wins on Sept. 1, the young right-hander admitted he would've laughed it off. Wells has taken it one pitch at a time.
"I was focused on doing my job and the rest will take care of itself," he said. "I'm not trying to reach any plateaus or win any awards. Every time they give me the ball, I just go out there and try to do my job."
The only run off Wells came in the Astros' seventh and was unearned. Kaz Matsui singled, stole second, moved up on an error by second baseman Jeff Baker and tallied on a groundout by Chris Coste.
Bradley belted his 12th homer with one out in the Chicago fourth. Alfonso Soriano, making his first start in three games after receiving a cortisone shot in his left knee, singled with one out in the fifth. He reached third on a throwing error by shortstop Miguel Tejada, who misplayed Baker's ball. Koyie Hill then hit an RBI single to make it 2-0.
Bradley singled to lead off the sixth and reached third on a questionable error by right fielder Hunter Pence, who couldn't get his glove on Derrek Lee's fly ball. Bradley scored on Ramirez's single. Kosuke Fukudome added an RBI double with one out in the eighth.
The win was the Cubs' ninth in their last 25 games, and they remained six games back in the National League Wild Card. The goal for the Cubs' final 32 games?
"Win as many games as we can, play as well as we can," Piniella said. "That's what I'm looking for and nothing else. We'll see where that takes us."
Ricketts has to be as disappointed as Piniella in how the Cubs' season has played out.
"I like to win, so I think from that perspective, I thought we could've done better," Piniella said. "I don't like to use the word 'disappointment.' I've gotten effort here. I know that these guys have done the best they can."
Wells said the Cubs haven't given up.
"I think we'll battle to the end and see what happens," the rookie said. "I don't think anybody is going to pack it in and say it's out of reach. I don't think that's the way the game's played. I think that's why everybody is here is because nobody thinks like that. We'll battle it out to the end and see what happens."
And if critics want to take shots at Piniella, he's ready.
"I've said, if you want to blame somebody, blame me," the Cubs manager said. "Blame me for the whole thing. I've said it before and I'll say it again. I've managed the same way I've always managed. I've let guys play, I play people I think should be on the field.
"I give everybody an opportunity, and we stay out of their way as much as possible. Sometimes things don't work out. This year it's been a struggle."