Pittsburgh (25-29) at St. Louis (33-23)

St. Louis rookie Joe Mather had a memorable debut replacing Chris Duncan. Now, Mike Parisi will get a chance to fill in for a struggling Cardinals veteran.

Parisi will make his first career start when the Cardinals continue their four-game series with the visiting Pittsburgh Pirates on Saturday night.

Due to sporadic hitting and spotty play in left field, Duncan was optioned to Triple-A Memphis on Friday. Mather was recalled from Memphis to replace Duncan, and he gave St. Louis (33-23) an instant spark.

Mather hit an RBI single and made a diving catch in right field, fully extending to rob Adam LaRoche of a likely RBI double, helping the Cardinals beat the Pirates (25-29) 5-4 on Friday night in the opener of this series.

The 25-year-old Mather, a third-round pick in 2001, batted second and helped St. Louis win for the sixth time in eight games.

Mather was batting .315 with 12 homers and 24 RBIs in 38 games for Memphis. He combined to hit 31 homers last season between Double-A Springfield and Memphis, and was nearly called up earlier this month.

“The first thing that comes to mind is, obviously, I’ve been in the minor leagues a while,” he said. “It’s been a long road but I’m here and it feels great.”

St. Louis has had to deal with lineup changes and injuries all season, particularly with its rotation.

Parisi (0-1, 2.87 ERA) will take the mound in place of Joel Pineiro, who was put on the 15-day disabled list Wednesday because of a strained right groin. This will be the right-hander’s first appearance against Pittsburgh.

Parisi, 25, was the opening day starter at Triple-A Memphis and was 2-1 with a 4.41 ERA in six starts in the minors. He has made eight relief appearances for the Cardinals.

Some early run support could help Parisi settle down. Albert Pujols has homered in three of his last four games, hitting his 14th of the season Friday. The star slugger has 10 hits in his last 18 at-bats, raising his average to .364.

Pujols is batting .455 (5-for-11) with a home run and a double versus Paul Maholm (2-5, 5.11), who will start for the Pirates. He is 0-3 with a 6.89 ERA in his last five outings, and is 0-4 with an 8.57 ERA in four road starts this season.

The left-hander pitched at St. Louis on May 14, allowing four runs and 11 hits in six innings as Pittsburgh lost 5-1. He is 1-3 with a 3.03 ERA in five starts versus the Cardinals.

In his last start, he gave up five runs and eight hits in eight innings as Pittsburgh beat the Chicago Cubs 6-5 in 11 innings on Sunday.

Maholm will be trying to spark a Pirates team that has lost three of four, allowing 25 runs in that span. With Maholm struggling, Pittsburgh’s lineup may need a big game.

Center fielder Nate McLouth is 4-for-24 against the Cardinals this season, but has three homers and five RBIs. He hit a solo homer Friday.

Pirates outfielders lead the majors with 34 homers.