The fight for a National League wild card playoff berth moves to Busch Stadium this weekend, where the St. Louis Cardinals and Pittsburgh Pirates open a three-game series tonight.
The Pirates enter the set holding a one-game edge over the Cardinals for the second of the NL's two wild card slots. St. Louis trails Pittsburgh by a single game and is five games behind Atlanta, which holds the No. 1 spot.
The Pirates and Cardinals are six and seven games, respectively, behind the Cincinnati Reds in the NL Central Division race. Pittsburgh gained a game with a win Thursday against Los Angeles, while the Reds were beaten by the New York Mets.
St. Louis missed a chance to advance with a loss to Arizona.
California-born right-hander James McDonald takes the mound for the Pirates while making a fifth try at an 11th victory of 2012.
The 27-year-old improved to 10-3 with a 9-6 win at Colorado on July 18, but has since gone 0-2 in four starts while his earned run average has soared from 2.93 to 3.77.
He's pitching on an extra day's rest after manager Clint Hurdle moved red-hot veteran A.J. Burnett into his slot for the finale of the series against the Dodgers and pushed McDonald back to face St. Louis.
A nine-game winner in 31 starts last season, McDonald is 1-2 with an 8.71 ERA since the All-Star break after going 9-3 with a 2.37 ERA in 17 starts in the first half.
He's 2-1 in eight career meetings - four starts - with St. Louis.
The Cardinals reply with veteran Jake Westbrook, who's won five straight starts to equal last season's win total.
Now 34 years old, Westbrook won 12 times in 33 starts with the Cardinals in 2011 - the first time he'd won a dozen games in a season since 2006 with Cleveland.
He earned his first career victory in his 11th career game against the Pirates on July 1, when he scattered nine hits and four runs over six innings of a 5-4 triumph.
Overall against Pittsburgh, he's 1-5 with a 5.18 ERA in 48 2/3 innings.
On Thursday in Pittsburgh, Garrett Jones clubbed a pair of three-run home runs to power the Pirates past the Dodgers, 10-6.
Clint Barmes knocked in three runs and Pedro Alvarez added a solo shot among his three hits, as Pittsburgh salvaged the finale of a four-game set and snapped a nine-game losing streak against the Dodgers.
A.J. Burnett (15-4) allowed six runs on seven hits and one walk while striking out seven over 6 2/3 innings to earn the victory, becoming Pittsburgh's first 15-game winner since Todd Ritchie went 15-9 back in 1999.
"He was laying it all out there," Hurdle said. "It was gritty all over the place (Thursday) for us."
In St. Louis, back-to-back homers by Paul Goldschmidt and Chris Young on consecutive pitches in the top of the ninth inning lifted Arizona to a 2-1 win over the Cardinals in the finale of a three-game set.
After Jason Motte (4-4) struck out Miguel Montero to begin the frame, Goldschmidt smacked a long ball into the left-center field seats and Young followed with a blast to left.
Allen Craig tallied an RBI single in the fifth frame to account for the Cardinals' lone run.
Starter Kyle Lohse, looking to extend his winning streak to seven games, fanned five and allowed four hits and three walks over 6 2/3 scoreless frames.
St. Louis won five of the first nine games between the teams in 2012, but the Pirates won two of three in the most recent series from June 29-July 1 at Busch Stadium.
The Cardinals won last year's season series, 9-7, while Pittsburgh last won in 2008.