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The Texas Rangers try to get one step closer to winning a game series with the Oakland Athletics at the Coliseum.

The Rangers come into tonight's opener holding a five-game lead on the Los Angeles Angels of Anaheim with a magic number of five to clinch the division. Texas won for the sixth time in seven tries on Sunday, as Adrian Beltre hit a two-run homer to back 6 2/3 scoreless innings from Matt Harrison, helping Texas defeat the Seattle Mariners, 3-0.

Harrison (13-9), who gave up six hits, won his third straight start for the Rangers. The Rangers have five pitchers, all starters, with at least 13 victories in 2011 for the first time in franchise history.

"He kept the ball down, did a good job of changing speeds," Rangers manager Ron Washington said of Harrison. "He handled the left-handers pretty good today in that lineup and got us where we needed to get in that game."

Elvis Andrus went 3-for-5 with an RBI double for the victors. He extended his hitting streak to 12 games.

Heading to the hill for Texas tonight will be lefty Derek Holland, who is 14-5 with a 4.02 ERA. Holland won his third straight decision on Wednesday against Cleveland, as he allowed a run and six hits in seven innings.

Holland beat the A's the last time he faced them and is 2-1 in eight games (five starts) against them with a 2.03 ERA.

Oakland, meanwhile, will counter with righty Rich Harden, who is 4-3 with a 4.76 ERA. Harden lost to the Angels on Wednesday, as he surrendered three runs and seven hits in 5 1/3 innings.

Harden, who pitched for the Rangers last season, is 5-3 lifetime against his former team with a 4.78 ERA in 14 games, 13 of which have been starts.

Oakland split a four-game set with the AL Central-champion Detroit Tigers over the weekend, but dropped a 3-0 decision to Justin Verlander in Sunday's finale.

Guillermo Moscoso (8-9) lost despite giving up only one hit -- an Austin Jackson homer to lead off the sixth.

It wound up being Moscoso's last frame. He walked two while fanning eight.

"He threw the ball really well," A's manager Bob Melvin said of his starter's performance. "You know when you go out there against a guy like Verlander, you're going to have to pitch well and you're going to have to keep runs to a minimum. And he did."

Texas is 11-5 versus the A's this season.