Prior to Sunday's game at Miller Park, Milwaukee's Ryan Braun will almost certainly be selected to his fifth All-Star game.
Gallardo looks to earn his seventh victory in as many regular-season starts against the Diamondbacks when he takes the ball for the finale of a three-game series.
Braun has put aside any possible distractions stemming from his overturned 50-game drug suspension in the offseason, and is batting .313 with an NL-best 22 homers and 55 RBIs.
"It's been good so far," said the reigning NL MVP after hitting two home runs in Saturday's 10-2 win over Arizona. "The one thing that challenges me is plate discipline and sometimes I've been swinging out of the strike zone. But overall, I am happy with where I am at."
Although Braun is enjoying another All-Star caliber season, it hasn't led to much success for the Brewers. Milwaukee (35-42) is eight games behind NL Central-leading Cincinnati, and Saturday's win was just its second in the last seven games.
With Gallardo (6-6, 4.14 ERA) taking the ball Sunday, though, the Brewers appear in good shape to pick up another victory.
Gallardo has compiled a 1.21 ERA while winning all six of his regular-season starts against the Diamondbacks (39-38). He also started Games 1 and 5 of last season's NL division series between the clubs, going 1-0 with a 1.29 ERA to help lead the Brewers to the NLCS.
The right-hander gave up one run and five hits in 7 1-3 innings of a 7-1 victory in Arizona on May 25.
Gallardo last pitched Monday in Cincinnati, giving up two runs, four hits and four walks in six innings of a 3-1 loss. Milwaukee's opening day starter has yielded three runs or fewer in nine of his last 10 outings.
While Gallardo has time and again overpowered the Diamondbacks, Arizona's Josh Collmenter (0-2, 4.80) has had Milwaukee's number.
In two regular-season starts against the Brewers last year, Collmenter went 1-0 while allowing six hits and a walk over 14 scoreless innings. He also took the ball in Game 3 of last October's NLDS after the Diamondbacks had dropped the first two games in Milwaukee, and gave up a run and two hits in seven innings of an 8-1 victory.
Braun was 0 for 2 with a walk against Collmenter in the postseason game, and has never faced him in the regular season.
Collmenter is starting in place of Daniel Hudson, who was placed on the disabled list Wednesday with a tear in the ulnar collateral ligament of his right elbow. Collmenter opened the season in Arizona's rotation, but moved to the bullpen after recording a 9.82 ERA in four starts.
The righty has performed well in relief and also in an emergency start June 22, when scheduled starter Joe Saunders felt tightness in his shoulder while warming up. Collmenter permitted one run and three hits in four innings of the Diamondbacks' 6-1 victory over the Chicago Cubs.
Arizona lost Saturday for the third time in five games after winning 12 of its previous 17.
Justin Upton walked twice but saw an eight-game hitting streak, in which he hit .467 with two homers and 10 RBIs, come to an end. He is 4 for 12 lifetime against Gallardo.
Copyright 2012 by The Associated Press
This story is from ESPN.com's automated news wire. Wire index
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