At the moment, they're teams headed in different directions.
"That's the way it's going to be," Santana said. "We're going after each other pretty good. Unfortunately for both teams we're in the wrong division. At the same time, that's what made this game so interesting."
The Twins have won 33 of their last 41, while the White Sox suffered their 11th loss in 14 games. Chicago is 7½ games behind first-place Detroit in the AL Central, and the Twins are another game out in third. And the White Sox lead the New York Yankees by one-half game in the wild-card race, with Minnesota right behind.
Bartlett broke a 1-1 tie when he hit his first homer of the season with one out in the seventh. Chicago's Joe Crede hit a two-run homer in the bottom of the inning to make it 4-3.
Santana (12-5) allowed three runs and seven hits while striking out six and walking none. He is 8-1 in his last 10 starts against the White Sox.
Contreras (9-3) allowed four runs and seven hits in seven innings, taking his third straight loss after winning a franchise record 17 straight regular-season decisions.
"I knew on a night like tonight I had to be perfect," Contreras said through an interpreter. "Either of us who made a mistake -- (the other team) was going to capitalize on it. In the seventh inning in a tight ballgame, I was the one that made the first mistake, and that's why they got the upper hand."
Joe Nathan put two runners on with one out in the ninth but got the last two outs for his 20th save in 21 opportunities. Michael Cuddyer robbed A.J. Pierzynski of the potential game-tying single with a diving catch in right before Alex Cintron grounded out to end the game.
"One thing about the Minnesota Twins," White Sox manager Ozzie Guillen said, "that's what they are right there: great pitching, clutch hitting and great defense. And I think that's the reason those guys have had success for so many years."
The winning rally started when Rondell White singled up the middle and Jason Tyner reached on a bunt single in front of the mound -- barely beating Contreras' throw. Bartlett then gave the Twins a three-run lead when he homered to left.
"The last guy I thought was going to hit a home run on the ballclub did," Guillen said.
Bartlett was surprised, too. He had not gone deep since last Sept. 13, against Detroit.
This one came on a hanging slider -- one that Bartlett got under a little bit. Although he made solid contact, he said he thought the ball would be caught.
Chicago's Jim Thome his a solo homer in the first -- the 463rd of his career and 33rd this season.
The Twins' Jason Kubel led off the second with his eighth home run to tie it 1-1.
"We always knew we are a good team," Nathan said. "We never lost sight of that."
- Minnesota's Nick Punto extended his career-high hitting streak to 17 with a single in the first.
- Twins CF Torii Hunter will likely be back in the lineup on Monday against Texas. Hunter, who has missed 10 games with a stress fracture is eligible to come off DL on Monday.
- C Joe Mauer will be the DH Wednesday, Twins manager Ron Gardenhire said.
- Twins OF Lew Ford, on the DL with a strained oblique muscle, will likely begin batting practice on Friday.
- White Sox backup C Sandy Alomar Jr. started his first game since being acquired in a trade with the Los Angeles Dodgers on Sunday.
- Chicago's Pablo Ozuna ended an 0-for-17 skid when he doubled in the third.