ANAHEIM, Calif. -- The Houston Astros are well ahead of their colleagues in the American League West, leading the Los Angeles Angels by 5 1/2 games after their 5-3 win on Sunday at Angel Stadium.

But the Astros to a man promise they will not get ahead of themselves and start thinking a 21-11 record on May 7 guarantees their future.

They clearly have a secure hold on the division. They are 17-6 after their first run of divisional play, winning eight of 10 series to date and all seven against AL West teams.

"More than who we're playing, it's how we're playing," said Jose Altuve, who had the key three-run homer in the third inning that put the Astros ahead to stay. "Winning every series we play is what it's all about.

"And we're not depending on any one player, we're a team. Every day it's a different player stepping up with a big hit or big play."

The Astros hit two home runs. Evan Gattis added a solo shot in the seventh to make it 5-3.

Houston's stout bullpen did its job, too. James Hoyt, Will Harris (two innings) and Ken Giles threw four scoreless innings in support of starter Mike Fiers.

"Jose was good," Astros manager A.J. Hinch said of his second baseman, who didn't start Saturday as Hinch chose to give him a day of rest. "I think the day off was good for him mentally. He gave us that big momentum shift, from their dugout to our dugout."

Los Angeles' Yunel Escobar took Fiers deep twice, to open the first inning and again in the fifth.

Fiers (1-1) has allowed an AL-high 14 homers this season in 30-plus innings, but he worked around Escobar's homers and four walks to leave with the lead after five innings. Fiers gave up three runs and four hits while striking out one.

"It's been my downside this year," Fiers said of the home runs. "(Escobar) hit my first pitch and I told myself I can't let up at any time. Each pitch is crucial. I wasn't making quality pitches in the second, but I battled."

The Houston bullpen has nine wins and 11 saves this season.

"It's always a good thing to play well against teams in your division," Harris said. "We're not going to be playing them again in a while, but I think they'll be better the next time we see them."

The Angels lost for the fourth time in five games. starter Matt Shoemaker (1-2) pitched six-plus innings, his second-longest outing of the season, but two of the five hits he allowed were home runs accounting for four runs. He yielded five runs, walked three and struck out four.

"Right now, he's still finding himself and making some bad pitches, and he's paying the price," Angels manager Mike Scioscia said of Shoemaker, whose 2016 season ended when he suffered a fractured skull when hit by a line drive.

"We know what Matt is capable of, and I think he'll get to that point soon."

The Angels were thrilled with the way they started the game. Shoemaker picked off Altuve to end the top of the first, and Escobar started the bottom of the inning with a booming home run to center off Fiers.

The Angels pushed another run across in the second to take a 2-0 lead. Cameron Maybin walked, stole second and went to third on Gattis' throwing error, and scored on Martin Maldonado's two-out single.

But the Astros unloaded on Shoemaker for four runs in the third. Alex Bregman doubled to left and Shoemaker walked George Springer with two outs. Josh Reddick singled off the right field wall to score Bregman, and Altuve hit Shoemaker's next pitch well up into the grandstand in left field for a three-run homer and a 4-2 Astros lead.

Escobar went deep on Fiers again in the fifth, this time to right center, to cut the Astros' lead to 4-3, but Gattis opened the seventh with a home run off Shoemaker to push it back to a two-run lead.

NOTES: Angels CF Mike Trout took a second day off with tightness in his left hamstring. He has missed three of the last four games. Trout said he expects to play Monday when the Angels visit Oakland. ... Houston 2B Jose Altuve extended his hitting streak at Angel Stadium to 17 games dating to June 2015. ... Astros 3B Alex Bregman extended his hitting streak to nine games, and he has a hit in 15 of his last 16. ... 2B Danny Espinosa returned to the Angels' lineup and extended his slump to 0-for-27. He went 0-for-2 with a walk.