The Los Angeles Angels' best run of the season has them as close to the AL West lead as they've been in nearly two months.
The Texas Rangers still hold that spot, but they're heading in the wrong direction.
Dan Haren will try to win his third consecutive start Sunday when the Angels go for their first sweep of the Rangers since 2009.
Last in the West on May 21 - and eight games back of Texas (31-22) - the Angels (28-26) have since won 10 of 11 to close within 3 1/2 games of the two-time defending AL champs, who have lost a season-high four straight.
Los Angeles, a season-best two games above .500 following Saturday's 3-2 victory, hasn't been this close to the lead since it was 3 1/2 behind the Rangers on April 14.
The Angels will try to continue their push up the standings - and earn their first sweep of Texas since Sept. 28-30, 2009 - with Haren (3-5, 3.52 ERA) facing Texas for the first time in 2012.
Sunday was originally supposed to be Jered Weaver's turn in the rotation, but after the Angels ace went on the disabled list Tuesday with a lower back strain, Haren will be working on normal rest.
Since posting a 5.79 ERA while losing a career high-tying four consecutive starts, the three-time All-Star has allowed one run in 16 innings over his last two outings. He's struck out 21 and walked none during that stretch after fanning seven in seven innings of one-run ball in Tuesday's 5-1 victory over the New York Yankees.
Haren went 0-2 with a 6.29 ERA in four starts against Texas in 2011, but he'll now be facing a Rangers team trying to avoid its first five-game skid since June 11-16 - its longest losing streak of 2011.
Texas might be able to snap out of its current funk by playing better defense. The Rangers have committed 14 errors in their last 13 games and have allowed 30 unearned runs - 27 since May 1 - to tie San Francisco for the most in the majors.
"You'll see tomorrow if I made a difference," manager Ron Washington said after holding a closed-door meeting following Saturday's game. "So much happened out there that was totally uncharacteristic of what we are, and it just opened up opportunities for the Angels to get some runs on the board."
Third baseman Adrian Beltre committed one of the Rangers' three errors Saturday and his 10-game hitting streak ended as he struck out a career high-tying four times, but he should have plenty of confidence stepping in against Haren. Beltre is 24 for 53 (.453) with three homers, a triple and seven doubles off Haren. It's the most hits by Beltre off any pitcher, as well as the most Haren has surrendered to any hitter.
Opponents haven't had much success lately against scheduled Rangers starter Matt Harrison (6-3, 4.41), who will try to match a season high by winning a third consecutive start.
The left-hander has a 1.80 ERA in his last two outings after throwing eight innings of two-run ball in Monday's 4-2 victory over Seattle.
Harrison, though, is 1-2 with a 5.34 ERA in five career starts against the Angels after giving up all of the runs in a 4-2 home loss May 12.
Mark Trumbo, who hit a two-run home run off Harrison in that game - Los Angeles' lone victory during last month's three-game set in Arlington - is 0 for 8 in this weekend's series after homering in each of his previous four games.
Angels outfielder Mike Trout is 4 for 8 with three RBIs in this series and batting .421 (8 for 19) off Rangers pitching in 2012.
Texas hasn't been swept on the road since last June 14-16 against the Yankees.
The Angels have won 13 of 19 at home since opening 2-5 in Anaheim.