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While their two main competitors for the National League Central crown go head-to-head this week, the Pittsburgh Pirates hope to get Jeff Locke on track Tuesday night in the opener of a three-game series versus the Milwaukee Brewers.

The Pirates dropped the final two contests of a four-game series with the San Francisco Giants, exiting play on Sunday tied with the St. Louis Cardinals for the top spot in the division, with the Cincinnati Reds 2 1/2 games back.

While Pittsburgh was off on Monday, the Reds and Cardinals opened up a three- game set in St. Louis. The Cards picked up an 8-6 win, moving them a half-game in front of the Pirates.

The Pirates were unable to score a run in Sunday's 4-0 loss in San Francisco as the Giants' Ryan Vogelsong hurled eight scoreless innings. A.J. Burnett took the loss, giving up four runs over 7 1/3 frames.

"He's pitched big games, he's won big games," said Pirates manager Clint Hurdle, referring to Vogelsong. "We weren't able to adjust or complicate things for him very much."

The Pirates will now host the Brewers and Cards for three games this week and hope that Locke can secure his first win since July 21.

The All-Star is winless in six straight starts, going 0-2 with a 6.59 earned run average. He lasted just four innings at San Francisco on Thursday and gave up three runs on five hits and four walks over 73 pitches.

Locke is 9-4 with a 3.01 ERA in 25 starts this season and beat the Brewers with six scoreless innings on May 25. He fanned seven, moving to 1-1 with a 4.50 ERA in three lifetime meetings.

The 25-year-old southpaw will also try to keep up Pittsburgh's recent success in this series. The Brewers went 59-18 versus the Pirates between 2008-12, but Pittsburgh has won five straight and nine of the 13 encounters this year, going 6-1 at home in that span.

Kyle Lohse, though, could be an equalizer as the first-year Brewer takes the hill tonight. He has excellent career numbers versus the Pirates, going 9-2 with a 3.35 ERA in 19 meetings (18 starts).

Lohse has won four of his past five decisions and beat his former Cardinals club on Tuesday. The right-hander allowed three runs over six innings of a 6-3 decision.

"I don't put any more emphasis on any one game over the other," said Lohse when asked about pitching against the Cardinals. "I went out there and tried to do what I've been doing."

That has been win. The 34-year-old Lohse is 9-8 with a 3.22 ERA in 26 starts this year, while 13 of his last 16 outings have been quality starts.

The Brewers lent the Pirates a hand by taking two of three from the Reds over the weekend, winning Sunday's rubber match 3-1 behind a great effort from Marco Estrada.

Estrada only allowed one hit through seven scoreless innings, walking two and striking out a season-high nine batters.

"It would have been nice," said Estrada about his chances to finish the game. "But with the weather the way it was, I was a little tired. Seven innings was pretty good."

Caleb Gindl slugged an early two-run homer and Jean Segura finished with two hits and drove in the other run for the Brewers.