Lohse pitched seven innings of three-hit ball to earn his seventh consecutive win, and the Cardinals beat the Houston Astros 4-2 on Wednesday night.
Lohse (13-2), who could become a free agent after this season, gave up two runs and retired his last 14 batters. He is 7-0 with a 2.21 ERA in 12 starts since he dropped a 3-2 decision against Kansas City on June 15.
"I felt really good," he said. "I felt in command."
The Cardinals have won consecutive games to grab a half-game lead on Pittsburgh for the second wild-card spot in the National League.
St. Louis manager Mike Matheny said he is not immune to scoreboard watching at this time of the year.
"We're fans of the game," he said. "We do pay attention. We try not to look up there too often because we do believe we control our destiny by how we play the game.
"But it would be a lie to say we didn't pay attention to what other people in the league are doing."
Jay also helped save the game with a leaping catch at the wall on a drive by Brett Wallace with one out in the sixth.
"He just did everything right," Matheny said of Jay. "He's just an impressive player. He's aggressive out there, and fun to watch."
Wallace and Chris Snyder homered for the Astros, who are winless in three games under interim manager Tony DeFrancesco. Houston, which dropped to 12-50 on the road, has lost six straight and is just 7-42 since June 28.
Bud Norris (5-11) allowed three runs and seven hits in six innings to fall to 0-10 with a 6.78 ERA in his last 14 starts.
"I didn't have my best slider tonight but I worked both sides of the plate with my fastball and tried to make some pitches," Norris said. "They snuck a couple across and they got the win."
Wallace went deep in the first and Snyder connected in the third to give the Astros a 2-1 lead. In his previous three starts in August, Lohse had allowed a single run in 19 2/3 innings of work.
"I threw a slider trying to throw it on Wallace's hands and it broke straight down and kind of right on his bat," Lohse said. "That was a mistake. Then I left one up for Snyder. Other than that, I felt like I made my pitches."
St. Louis went ahead for good in the fifth. Rafael Furcal hit a leadoff single, moved up on Lohse's sacrifice and scored on Jay's single to right. Jay eventually scampered home on a wild pitch to make it 3-2.
Molina singled in Matt Holliday in the eighth.
Jake Westbrook (12-9) will pitch for the Cardinals in the series finale against Dallas Keuchel (1-5). St. Louis announced a $9.75 million, one-year contract with Westbrook on Tuesday that includes a mutual option for 2014. ... Houston's Jose Altuve had a double to give him 139 hits, tops among second baseman in the NL. ... Lohse had not allowed two home runs in a game since a 10-7 loss against Atlanta on May 30.