ST. LOUIS -- The St. Louis Cardinals could be on the verge of adding a major piece to their lineup, just in time for their battle to secure a wild-card spot in the playoffs.

Shortstop Aledmys Diaz could be activated from the disabled list as early as Sunday. Diaz has been out since he broke his right thumb when he was hit by a pitch by the Marlins' Andrew Cashner on July 31.

Diaz has been on a rehab assignment with Double-A Springfield. He played his third game on Saturday in the Texas League playoffs and was 0-for-5 as the Cardinals lost 3-2 in 10 innings and lost the series to Northwest Arkansas.

At the time he was injured, Diaz was hitting a team-leading .312 with 14 homers and 57 RBIs in 96 games, earning a trip to the All-Star Game and making himself one of the leading candidates for the National League Rookie of the Year award.

In his absence, the Cardinals have split the playing time at shortstop between Jhonny Peralta (eight games, all in early August), Greg Garcia (13 contests) and Jedd Gyorko (15 games). The team has gone 19-17 in the 36 games that Diaz has missed.

"We don't want to put pressure on him that he all of a sudden has to be the guy that catapults us into another level," manager Mike Matheny said on Saturday. "We just want to get him healthy. We just want to get him back to where he was, because where he was was pretty impressive."

Diaz's return will force Matheny to juggle his starting infielders. Gyorko, who leads the team with 26 home runs, 19 since the All-Star break, likely will slide to either second or third, which could put either Kolten Wong or Peralta on the bench.

Matt Carpenter also can play both second and third, but he also has been getting frequent starts lately at first base.

Rookie Luke Weaver, who is 1-2 in five starts, will get the start for the Cardinals in the series finale on Sunday against the Brewers, who will start Zach Davies, who is 10-7.

St. Louis scored all of its runs in the eighth inning in a 5-1 win over the Brewers on Saturday night. The Cardinals moved back into the second wild-card spot, a half game ahead of the New York Mets, who lost 4-3 to the Braves in 10 innings.

The Brewers' only run came on a home run by Keon Broxton, his seventh of the season.

"I feel like I can just play my game right now and it took a while to get here, but I just feel comfortable and keep on playing," said Broxton, who has posted a .314 average since July 25. "It's all about getting a good position to hit. I've found a pretty solid foundation to hitting and it's all about seeing the ball and squaring it up."

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