Fielder hit two of the Rangers' season-high five homers and drove in five runs, Napoli went deep along with his first career outfield assist and the Rangers extended their division lead over the Houston Astros with a 14-3 victory Wednesday night.
"We can't let up now, we've still got games to play," Fielder said.
"Complete focus and determination. This was a buildup getting to this point," manager Jeff Banister said. "This is not an exhale moment. This is putting a foot down, continue to do your yard work, stay focused."
After winning in their final at-bat the previous two nights, the Rangers took a 6-0 lead in the first off Dallas Keuchel (17-8), the left-hander who was the AL starter in the All-Star Game this summer and entered the game as the league's ERA leader.
Fielder's RBI single in the first put the Rangers ahead to stay. The slugger pulled both of his homers into the second deck in right field, leading off the third against Keuchel and then capping an 11-pitch at-bat in the sixth off reliever Michael Feliz with a three-run shot that made it 12-1.
Rougned Odor and Bobby Wilson homered for Texas (78-67), which won its third straight game in the series. The Rangers, who took over first place with a 6-5 win Tuesday night, lead Houston by 1 1-2 games going into the series finale Thursday.
Martin Perez (3-5) gave up one run over seven innings while allowing 10 base runners — nine hits and a walk. The lefty struck out three.
"Our guys are very well aware of where we on in the calendar and what we need to do to make things better. We've come this far. We've earned it," Houston manager A.J. Hinch said. "We're still having a good time, we're just not enjoying the defeats, but we have some time to correct it and salvage a game tomorrow."
Fielder had a one-out single in the first and then scored on Napoli's three-run homer. Odor added a two-run shot, his 14th.
It was Napoli's 17th homer this season, fourth since Texas reacquired him from Boston on Aug. 7. The latest led to chants of "Nap-o-li!, Nap-o-li!" as were popular when the slugger was part of the Rangers' last World Series run in 2011.
Napoli played his third professional game in left field. That's how Banister gets that bat in the lineup and stretch the Rangers lineup against left-handed starters.
But Napoli also had a nifty defensive play in the third, when he picked up the ball that ricocheted off the wall down the left-field line and threw out Hank Conger trying to go to third base.
Keuchel's ERA rose from 2.22 to 2.56 after he allowed a career-high nine runs and 11 hits over 4 2-3 innings. He struck out five without a walk while giving up three home runs, matching a career high.
"I knew they were going to be aggressive," he said. "I thought I made a few quality pitches there, but they put some good swings on some two-seams early. Kind of got me in a hole."
Fielder's two homers pushed his total to 21, making the ninth time in his career with at least 20 in a season. It was his 27th career game with multiple homers. ... Wilson homered for the first time since Aug. 31, 2012, while playing for the Los Angeles Angels. ... Evan Gattis hit a two-run homer for Houston.
Astros: C Jason Castro (right quad strain) missed his 17th game, but caught in the bullpen before the game. Hinch said there is a chance Castro could play in the series finale Thursday. ... OF Carlos Gomez (left intercostal muscle) did some exercises but didn't swing a bat. ... 3B Marwin Gonzalez (swollen left index finger, sore wrist) returned to the lineup after missing two games, but was replaced in the field in the fourth inning.
Rangers: C Robinson Chirinos is expected to swing a bat Thursday for the first time since re-aggravating a left shoulder strain last week.
Astros: Houston wraps up its season-long 11-day, 10-game trip. The Astros are 2-7 so far. They have lost the last three games started by rookie RHP Lance McCullers (5-5).
Rangers: RHP Colby Lewis goes for his career-best 16th win. He is coming off a shutout vs. Oakland when he needed only 97 pitches.
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