The Oakland Athletics waited until the last day of the season to win the AL West last year.
They're making their move earlier in 2013.
A day after pulling even with the visiting Texas Rangers, Oakland can move ahead of them for sole possession of first place on Tuesday night.
Coco Crisp's fifth-inning go-ahead home run - upheld by video review - was the difference maker in a 4-2 victory on Monday, Oakland's fourth in a row. Crisp's homer was his third in as many games and his career-high 17th of the year.
Crisp later left after fouling a ball off his shin but said he was fine afterward.
"It's a back and forth that kind of pumps your blood a little bit," Crisp said. "Obviously you want to be close or you want to be in front, in first place or as far in front as possible. We're fortunate we're in the situation we are now."
Oakland (79-58) spent much of the latter part of last season chasing Texas and only claimed the division crown on Oct. 3 with a 12-5 victory.
This season, Texas (79-58) had been in sole possession of first place since Aug. 10.
"I expect it to go all the way down to the end. Division champs over there," manager Ron Washington said after his club's third loss in its last 15 road games. "I don't expect them to go away and I certainly don't expect us to go away. Everything goes through Oakland. Doesn't matter where positioned in the standings right now."
The Rangers hope starter Martin Perez (8-3, 3.58 ERA) can extend his rookie club-record winning streak to six starts. His offense has played a big role in that stretch, supplying him with 40 runs of support in his last 35 1-3 innings, but he's also limited opponents to 12 runs over that span.
"He just goes out there and does what he does," Washington said. "That's throw the fastball down in the zone, change speeds and use his breaking ball and move it around."
Perez hasn't faced Oakland after going 1-2 in three starts last year. He won the first but then surrendered nine runs over 4 2-3 innings in the two losses.
Crisp is 2 for 6 off Perez with a double and two strikeouts.
Oakland will counter with Bartolo Colon (14-5, 2.94), who allowed one run over five innings of a 7-6 loss at Detroit on Thursday in his first start since Aug. 13. Colon had given up 10 runs over 6 2-3 innings in two starts before a stint on the disabled list due to a groin injury.
He is 2-1 with a 2.89 ERA in four starts against the Rangers since joining the Athletics in 2012.
Oakland may have to lean on a different pitcher in a potential save situation after Grant Balfour pitched for the fourth time in five days on Monday. Balfour, who allowed a hit and a walk before recording his 36th save, said he was running on fumes.
Lance Berkman was 0 for 4 for the Rangers in his first game since July 7 after being sidelined by left hip inflammation and a sore surgically repaired right knee. Washington told the team's official site he plans to start him Tuesday as well to see how he responds after the long layoff.
Adrian Beltre is batting .302 (19 for 63) with five homers and seven doubles lifetime versus Colon.