The designated hitter's tiebreaking, two-run homer in the eighth inning lifted the Rangers to a 5-3 victory over the Astros on Monday, pulling Texas within a half-game of Houston in the American League West.
Texas (76-67) opened the four-game series at Globe Life Park with its ninth win over Houston (77-67) in 13 meetings this year. The teams have three more games this week.
"It's always good, especially when you get the first one," Fielder said after his 51st multi-hit game this season. "They're a great team. They're first in our division, so it's good to get the first game and hopefully we can get the one tomorrow."
The game between the instate rivals had all the makings of playoff showdown, as both clubs sent ace left-handers to the mound. Texas set up its rotation to start Cole Hamels, while the Astros countered with Scott Kazmir.
However, the bats proved the difference, as the Rangers got two-run blasts from Fielder and first baseman Mitch Moreland.
"They hit some pretty opportunistic homers tonight," Houston manager A.J. Hinch said.
Fielder connected off reliever Will Harris (5-4) with one out in the eighth.
"I was just trying to get a good pitch to hit," Fielder said of his 19th homer. "He made a couple of good pitches there to get to 3-2. I was just trying to see a good pitch and put a good swing on it."
Hinch felt he had the right guy in there to face Texas' cleanup hitter.
"Will is a pretty good reliever," Hinch said. "He's had a good a year as any of them. He's handled lefties, handled righties. He just made a bad pitch."
Texas reliever Keone Kela (7-5) earned the win after getting the last out in the top of the eighth. Closer Shawn Tolleson picked up his 32nd save by throwing a scoreless ninth.
"We didn't play as clean as we have at some points during the year," Texas manager Jeff Banister said. "We had to grind and show some mental grit. We needed for some guys to show up big for us tonight, and they did."
Houston dropped to 29-43 on the road and 2-5 on its current 10-game road trip.
Moreland gave the Rangers their first lead of the game with a two-out, opposite-field home run to left off Kazmir in the sixth. Moreland's 20th blast of the season made it 3-2.
The Astros battled back against Hamels in the top of the seventh, stringing together several long at-bats before tying the game on left fielder Colby Rasmus' stinging single to right with two outs. The rocket off Rasmus' bat bounced before it ricocheted off Moreland's chest, allowing shortstop Carlos Correa to score from second.
Both Hamels and Kazmir pitched seven innings and allowed three runs while walking one and striking out four, though one of Texas' runs against Kazmir was unearned.
The Astros jumped on Hamels in the first inning, as Altuve deposited the first pitch he saw into the left field seats. Hamels had gone five straight starts without giving up a home run.
The Rangers tied it in the second thanks to an error to start the inning. Fielder reached after third baseman Jed Lowrie dropped a routine popup. Fielder scored on second baseman's Rougned Odor's two-out double to straightaway center.
Houston limited the damage and saved a run for Kazmir when Correa took a relay throw from center fielder Jake Marisnick and threw out Texas left fielder Mike Napoli at home.
Kazmir got himself out of a second-and-third, one-out jam in the third by getting third baseman Adrian Beltre and Fielder to pop out.
Houston took a 2-1 lead in the fifth on Marisnick's head-first slide around a tag by Texas catcher Chris Gimenez. Marisnick doubled and reached third on a Hamels balk before breaking for home on right fielder George Springer's sharp grounder to first. Moreland fired to the plate, but Marisnick got his hand under Gimenez's glove.
Lowrie left the game in the fifth inning with a shin injury. He was hit by a pitch in the first inning.
NOTES: On Monday, Texas and Houston began a stretch of seven games against each other in the next 14 days. The Astros held an eight-game lead over the Rangers in the AL West in early August. ... Houston selected the contract of INF Matt Duffy from Triple-A Fresno. (This is a different Matt Duffy than the one who plays third base for the San Francisco Giants.) To make room on the 40-man roster, RHP Scott Feldman (shoulder) was placed on the 60-day disabled list. ... Since the Astros and Rangers started playing each other in 2001, the clubs both had winning records in the same season just once, in 2004, when the Astros went 92-70 and Texas 89-73. ... Texas 3B Adrian Beltre and Houston OF George Springer are their clubs' nominees for the Roberto Clemente Award.