A weekend series between the NL Central's top teams begins with starters that figure to have some doubts.
The Brewers are mired in a season-worst five-game slide and the second-place Cardinals are within two games of the lead entering Friday night's opener of a three-game series at Miller Park.
St. Louis (50-43) has won six of nine to move into position of gaining first place at the All-Star break with a weekend sweep. Milwaukee (52-41) has dropped nine of 10 and will try to avoid its first six-game slide since June 26-July 1, 2013.
The Brewers are reeling after being swept in a four-game home series against NL East-worst Philadelphia, capped with Thursday's 9-1 rout.
''The longer it keeps going, the worse things go for us, it gets a little tougher,'' manager Ron Roenicke said. ''We'll come back (Friday), talk about some things and see if we can get this turned around.''
The problem is that Roenicke will give the ball to Gallardo (5-5, 3.45), whose 1-11 career regular-season mark against the Cardinals matches Mark Buehrle's record against the New York Yankees as the worst for active pitchers against one opponent with a minimum of 10 decisions.
Gallardo has a 6.34 ERA in those games. He's actually 1-12 with a 6.38 ERA against St. Louis in 19 overall starts, including one in the 2011 NL championship series, and he's 0-6 with a 6.75 ERA in nine home starts versus the Cardinals.
Milwaukee won for just the fourth time with Gallardo on the mound against the Cardinals in a 5-3, 12-inning victory April 28. He allowed three runs in six innings.
Matt Holliday has taken him deep more than any NL batter, going 10 for 33 with four homers.
The Cardinals will turn to Kelly (1-1, 0.59), who last pitched when he allowed an unearned run in four innings April 16 to suffer a 5-1 loss at Milwaukee. His hamstring strain didn't come from pitching but from running as he tried to beat out a bunt attempt.
"It's definitely a good day to come back," Kelly told MLB's official website. "I want to go back and pitch well there. It's exciting."
The right-hander has posted a 2.65 ERA in losing all three starts at Miller Park. Kelly gradually increased his pitch count in three rehab starts in the minors, throwing 72 for Triple-A Memphis on Sunday.
He won't have Yadier Molina as a batterymate after the Cardinals confirmed Thursday that the catcher will miss eight to 12 weeks. Molina tore a ligament in his right thumb in Wednesday's 5-2 win over Pittsburgh, and Tony Cruz started in his place in Thursday's 9-1 defeat.
''I think it was a tough night for our club in general,'' manager Mike Matheny said. ''We just didn't look right from the beginning.''
St. Louis first baseman Matt Adams has 14 hits in his last 29 at-bats.
Brewers slugger Ryan Braun went 1 for 4 on Thursday after missing two games with a sore back.