DETROIT -- "I wasn't looking for it," Justin Upton said, "but I saw it."
But what Upton got was a slow, fairly flat curveball that he waited on and swatted into the left field seats to give the Tigers a 7-4 victory over Chicago, Detroit's fourth win in a row and the fifth straight loss for the White Sox.
Robertson (3-2), who got the last out of the eighth, hit Nick Castellanos with a 2-2 pitch to begin ninth with the score tied at 4. He got Miguel Cabrera to hit a roller to second, but Yolmer Sanchez bobbled the potential double-play grounder and had to settle for the out at first.
J.D. Martinez was walked intentionally before Robertson served up Upton's 11th home run this season and fifth walk-off blast of his career.
Detroit completed its first series sweep of the season.
"We didn't play a really clean game of baseball," Chicago manager Rick Renteria said. "We had a couple plays that got away from us. We kept battling. All in all, I thought the guys were a little tired. Nonetheless, that's not an excuse for some of the mistakes that we made."
Justin Wilson (2-1) gained the victory after throwing a scoreless ninth. He gave a leadoff walk plus a single before wriggling out of the jam via a popup and a double play.
The White Sox tied the score 4-4 with three doubles off Tigers reliever Alex Wilson in the eighth. Todd Frazier hit the first double, and Tim Anderson and Devan Smith followed with run-scoring two-base hits. Pinch hitter Leury Garcia singled to center off reliever Daniel Stumpf to move Smith to third, but Tigers reliever Shane Greene entered and ended the inning by getting a strikeout and a forceout.
Upton led off a three-run Tigers sixth with a single, chasing reliever Anthony Swarzak. Upton scooted to third when Chris Beck made a wild pickoff attempt. John Hicks doubled to center to create a 2-2 tie and then stole third -- after pinch hitter Victor Martinez was walked intentionally -- when third baseman Frazier went in too far on a failed bunt attempt by pinch hitter Alex Presley.
Presley got Hicks in with an RBI grounder to second that Sanchez missed for an error. Jose Iglesias made it 4-2 when he grounded into a forceout to score pinch runner Andrew Romine from third, which he reached on the error by Sanchez.
"They're playing through it," Renteria said. "Some of our actions were a little slow. They're not trying to make mistakes. They're not trying to boot balls, they're not trying to get picked off, all those things, they're not trying to not miss executing on bunts.
"But it's something we really have to learn from. Because clubs that want to have success have to play clean baseball. We talked about it. Everybody has a chance to win a ballgame on a daily basis."
Reliever Warwick Saupold was big for Detroit for a second straight appearance, keeping a deficit at 2-0. He relieved starter Justin Verlander, taken out due to a right groin strain with two on and no outs in the third. Saupold pitched four scoreless innings.
"He was huge again for the second time in a row," Ausmus said. "He did it in Kansas City and he did it here -- giving us multiple innings, getting us deep in the game, keeping it close. He's been outstanding in that role."
Detroit cut the deficit to 2-1 when J.D. Martinez belted his 10th home run of the season with one out in the fourth off White Sox starter David Holmberg.
Chicago got a one-out double plus a two-out single by Avisail Garcia to take a 1-0 lead in the first but left the bases loaded in both of the first two innings.
Frazier touched Verlander for his eighth home run to lead off the third. After a subsequent four-pitch walk, Verlander was removed from the game.
Verlander struck out the first batter he faced to make it 327 straight starts in which he has had at least one, eighth longest such streak since at least 1913. He walked three, struck out three and gave up two runs on six hits.
NOTES: Detroit C James McCann (right hand cut) and 2B Ian Kinsler (left hamstring) are on track to be activated off the disabled list on Tuesday. ... Chicago RHP James Shields allowed three runs (one earned) in four innings during his first rehab start Saturday for Triple-A Charlotte. ... Tigers DH Victor Martinez has been dealing with a sore left elbow that bothers him most batting right-handed, so manager Brad Ausmus kept him out of the starting lineup against White Sox LHP David Holmberg. ... The White Sox announced midgame that RHP Carlos Rodon (left biceps bursitis) would begin a rehab assignment Tuesday.