Shin-Soo Choo homered and drove in three runs, and the Rangers beat Houston for the eighth straight time.
"There's no exhale," manager Jeff Banister said. "We're not going to look up until it's done. This is a mission. We're looking for an accomplishment to get to where we want to go. So you don't relax, you still play with that urgency."
Houston star second baseman Jose Altuve exited early after being hurt in a collision with shortstop Carlos Correa while chasing a popup. Manager A.J. Hinch said Altuve didn't have a concussion and hoped to play on Saturday.
"I felt a little dizzy at first, but now I feel good," Altuve said.
The Rangers improved to 16-7 this month, whereas Houston lost its third in a row and fell to 7-15 in September. The Astros' lead for the second AL wild-card spot was whittled to a half-game over the Los Angeles Angels, who beat Seattle 8-4.
"We have to find a way to do better," Hinch said. "Our guys are working. They are trying and prepared and doing everything they can. It's just that the results are not there for us right now, and it has piled up for us."
Scott Kazmir (7-11) yielded 10 hits and six runs, lasting just 3⅔ innings for the second straight game. He hasn't won since Aug. 22, a span of six straight starts.
Choo, who had three hits, put Texas up 3-0 with an RBI single in a two-run second. He added a two-run homer in the fourth.
"I play eight years in the big leagues, and I don't have any experience with first place late in the season," Choo said. "So I really enjoyed it, and then it makes me [have a] lot of energy."
Luis Valbuena hit a two-run homer in the fourth inning for the Astros, who have dropped eight of 11. Houston went 1-for-11 with runners in scoring position.
Altuve and Correa were tracking a popup by Elvis Andrus with two outs in the seventh. Altuve had the ball in his glove for a moment before Correa crashed into him.
Correa's glove hit Altuve in the face and knocked him to the ground.
Altuve used his right arm to break his fall. He grimaced as he remained on the field for a couple of minutes while trainers attended to him, and he eventually walked off the field.
"You get scared because he is one of our best players," Correa said. "When he said he was dizzy, I was like, 'Oh my,' but then we see that he is fine, and he is ready for tomorrow."
Texas got an RBI double by Prince Fielder to take a 1-0 lead in the first inning and has now won 13 straight games when scoring in the opening frame.
Mitch Moreland started the second with a double that rolled up Tal's Hill in center field. Kazmir overthrew first for an error on a bunt single by Andrus that allowed Moreland to score and push the lead to 2-0.
DeShields doubled with two outs in the fourth, and Choo launched his 19th homer into the first row of the seats in right field. Adrian Beltre doubled before an RBI single by Fielder chased Kazmir.
Astros: OF Carlos Gomez (intercostal strain) missed his 12th straight game. He hoped to return on Saturday, but Hinch isn't sure if he'll be ready. Gomez could be used as a defensive replacement or a pinch runner before he's healthy enough to get back in the lineup. ... Correa was in the lineup on Friday despite fighting a cold.
Banister went to high school in La Marque, Texas, which is about a 45-minute drive from Minute Maid Park. He played some football games at the Astrodome when he was in high school and figured out a way to sneak in to the building to see the Astros play back then. "I paid my $2.50 to park, and I found my way in through the loading dock because I didn't have anything past $2.50 and had to get enough gas in the car to get back home," he said. "Hopefully they don't ask me for a refund."
Banister loves that the two teams in Texas are the leaders in the division.
"As a kid who grew up in this city ... I'm just as proud of them as I am [of] us really just for the fact that I'd rather it be us two fighting it out," Banister said. "I'm still a fan, too, you know, deep down."
Rangers LHP Derek Holland (3-3, 4.75) opposes Collin McHugh (17-7, 3.93) when the series continues on Saturday. Holland looks to get back on track after going 0-2 with a 9.00 ERA in his past three starts, a stretch that has raised his ERA from 2.37 to 4.75.
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