• Hero: Zambrano (8-6) matched his career-high with 12 strikeouts and struck out the side in the first and third. He allowed one run and one walk in eight innings.
• Hard luck: Buehrle (4-4) once again pitched well without a win to show for it, allowing two runs in seven innings before being pulled after 116 pitches.
• Total freefall: The White Sox (29-40) dropped 11 games under .500 for the first time since May 29, 2001.
• Quotable: "He was throwing an 80 mph split, an 82 mph slider and 90 mph cutter, so that's why he's been as good as he's been for a long time. He's got incredible stuff. When he throws strikes and gets ahead, he's as tough as anybody."
-- A.J. Pierzynski, on Zambrano.
-- ESPN.com news services
Cubs 5, White Sox 1
CHICAGO (AP) -- Now, Carlos Zambrano is punching out the opposition.
Zambrano matched a career high with 12 strikeouts, leading the Chicago Cubs over the White Sox 5-1 Friday and sending their crosstown rivals to their 20th loss in 25 games.
Zambrano (8-6) took over from there, striking out seven of his first nine batters and finishing with 12 for the fourth time in his career. He allowed three hits and one walk in eight innings, striking out the side in the first and third.
"I put it in my mind that it's a new season for me," Zambrano said.
He improved to 3-1 in his last four outings -- in his previous start he lost 1-0 to San Diego after taking a no-hit bid into the eighth inning -- and his ERA has dropped from 5.62 to 4.27.
Zambrano is starting to build a case for his third All-Star selection -- a scenario that seemed unlikely on June 1.
He fought with Michael Barrett during a game against Atlanta that day, leaving the catcher with a black eye and a cut on his lower lip that required six stitches. Barrett also had a heated exchange in the dugout with Rich Hill less than two weeks later and got dealt to San Diego on Wednesday.
"You have to have pride," Zambrano said. "All players have to have pride. It was embarrassing, what I did to one of my teammates. ... I'm a good pitcher, and I have to settle down and shut it off, start a new season."
Ryan Dempster pitched a perfect ninth.
Buehrle (4-4) settled down after a rough first, allowing two runs and four hits in seven innings. He struck out four and did not walk a batter. He vomited after he left the game and was not available for comment.
The White Sox (29-40) dropped 11 games under .500 for the first time since May 29, 2001. Not that the Cubs (33-39) are much better.
Soriano started the game by sending a high, arching shot out to left on a 3-2 pitch. The ball landed an estimated 424 feet away for his 13th homer -- it was his fourth leadoff drive this season and the 36th of his career.
Mike Fontenot followed with a sinking liner to center. Darin Erstad, who had been on the disabled list since June 1 with a sprained left ankle, aggravated the injury when he made a diving catch. He stayed on the field but did not take his turn at bat in the bottom half of the inning. He left for an MRI exam, and the results are expected on Saturday.
"It's just crazy year," White Sox manager Ozzie Guillen said. "Crazy the way we are injured. We don't have too many days where we put the complete lineup together, the one we had in plans. Meanwhile, this ballclub is better, offensively better (than) to have three hits every day."
Ramirez, who had tendinitis in his left knee, was the designated hitter, and he made it 2-0 with a line drive that just cleared the wall in right for his team-leading 14th homer. He added an RBI single during a three-run ninth inning that extended the lead to 5-1.
"When Aramis is in the lineup, it's obvious," the Cubs' Derrek Lee said. "He came back strong, didn't miss a beat."
The White Sox did not reach base until Tadahito Iguchi singled to center with one out in the fourth. The only starter who batted but did not strike out was Pierzynski, who noticed a big difference in Zambrano from the last time he faced him. The White Sox tagged him for seven runs on their way to a 10-6 victory on May 20.
This time, Zambrano's fastball was in the mid-90s, which set up his splitter and slider.
"He was throwing an 80 mph split, an 82 mph slider and 90 mph cutter, so that's why he's been as good as he's been for a long time," Pierzynski said. "He's got incredible stuff. When he throws strikes and gets ahead, he's as tough as anybody."
Zambrano's name has come up in trade rumors, but he reiterated he wants to remain a Cub. And he's making a strong case to stay.
"He's picked up command of his pitches, stamina, the whole thing," Cubs manager Lou Piniella said. "It's really nice to watch. It's good stuff."
Zambrano had most recently struck out 12 against Florida on April 24, 2006. ... The Cubs sent reliever Sean Gallagher to Triple-A Iowa following Thursday's game at Texas. ... The White Sox expect OF Scott Podsednik (right adductor strain) back from the DL on Monday. He's rehabbing at Triple-A Charlotte. ... The White Sox fired senior director of amateur scouting Duane Shaffer after 35 seasons with the team.