DETROIT -- Rick Porcello fell just short of his first complete game.
He'll have to settle for a spot atop the AL Central.
The Tigers lead the White Sox by a half-game. It's the first time they've been in first since they were tied after beating Kansas City on May 1.
"On paper, you can say whatever you want, but if you don't perform on the field then it means nothing," Porcello said. "We all believed in each other, and we've still got a lot of work to do. This isn't over yet. This is just getting started."
Detroit was six games out after a loss to the Chicago Cubs on June 12.
Brennan Boesch hit a three-run homer and Austin Jackson drove in the other four runs for the Tigers. Porcello (7-5) has never thrown a complete game in the majors. He departed Saturday after allowing two hard-hit singles to start the ninth.
Porcello allowed a run and five hits. He struck out four with no walks, outdueling Chris Sale (11-3) in the Chicago left-hander's first loss since May 12.
"Just made some bad pitches at some bad times," Sale said. "A team like that is going to capitalize."
Sale allowed five runs and seven hits in seven innings. He struck out six and walked four. The Tigers will go for a three-game sweep Sunday, sending rookie Jacob Turner (0-1) to face Philip Humber (4-4).
Detroit was expected by many to win the division easily after finishing 15 games in front last year and adding Prince Fielder in the offseason. But the Tigers struggled through the first half of the season, and Chicago emerged.
Now the White Sox have lost four straight and six of eight. They seemed to have an advantage on the mound Saturday -- Sale was 8-0 with a 1.61 ERA in his previous 10 starts -- but that didn't materialize.
Porcello retired the first 12 hitters he faced. Chicago took the lead in the fifth on Dayan Viciedo's RBI single, but the Tigers answered quickly.
Boesch's homer the following inning also came with two outs, and so did Jackson's two-run single in the eighth.
"I know in my case, if I have two outs and the guy gets a big hit or something like that, that's the dagger," Porcello said. "It's one of the worst things you can go through. ... Our offense, the way they've been playing is really nice."
Since the All-Star break, the Tigers have scored 35 of their 48 runs with two outs, according to STATS, LLC. Before the break, they scored 129 of their 387 runs with two outs.
"The most important thing in baseball I think is pitching, defense and then two-out RBIs," Boesch said. "I don't know if we'll be able to sustain it to this pace, but you'd like to think that we're clicking at the right time."
Boesch struck out his first two times up against Sale before connecting for his 10th homer of the year.
"He's a tough lefty, obviously," Boesch said. "You have your work cut out for you all game. You just try to keep battling until you get a pitch you can handle."
The 23-year-old Porcello has had a rocky start to his career. He won 14 games for the Tigers as a rookie in 2009, but manager Jim Leyland has essentially admitted he was rushed to the big leagues.
A few more starts like Saturday's would give Detroit quite a lift down the stretch. The crowd gave Porcello a standing ovation when he came back to the mound for the ninth, but he wasn't able to finish for the elusive complete game. He threw 94 pitches, and the crowd repeated the warm ovation after Leyland lifted him.
The time of game was 2 hours, 11 minutes. ... Jackson's four RBIs equaled a career high set May 9, 2011, at Toronto. ... The Tigers have allowed five or fewer hits in four straight games, the team's longest streak since May 20-24, 1984.