Wells earned himself another start Tuesday from manager Mike Scioscia. The outfielder missed 55 games this summer with a right thumb injury and is no longer a constant in the lineup since returning July 27.
"The biggest thing is when I do get a chance to play just try to do what I can to help this team win, whether it's in the box or on the field," Wells said. "It was difficult at first. The more you go through it, you live for today. That's the best way to go through life -- enjoy the moment."
C.J. Wilson (11-9) pitched five innings while dealing with a blister and shut down the red-hot Athletics in the Angels' sixth victory in the last seven. Oakland had all the momentum coming off a commanding sweep of the Red Sox in which the A's outscored Boston 33-5.
"Our bats just overwhelmed them today," Wilson said. "That's the kind of offense we need to put up there to be relentless and put pressure on the other team."
Torii Hunter led off the third with a solo homer and added a sacrifice fly in the sixth for the Angels. Wells hit his 10th homer to start the fourth and No. 9 hitter Iannetta connected in the sixth.
Wilson outpitched fellow lefty Tommy Milone (11-10) to win back-to-back starts for the first time since June 19 and 26.
"They had some good at-bats off him right away and made him work pretty hard," A's manager Bob Melvin said. "When he threw the ball over the plate, they were hitting it hard."
Josh Donaldson hit a leadoff homer in the fifth and Josh Reddick added an RBI single for the A's, who lead the AL wild-card race. They have homered in 10 straight games and have 22 during that stretch.
Milone was knocked out of the game after giving up five runs in a season-low three innings. The rookie's 10 hits allowed matched the most he has given up this year and he lost for the first time in four starts.
"From the first inning on I didn't feel comfortable and was struggling to keep the ball low," Milone said. "I forced myself to throw strikes and when I do that I leave it up in the zone."
Trout also stole his AL-leading 43rd base in the sixth. Wells, not known to be the most patient at the plate, drew two walks, reached base four times, scored two runs and had his third steal.
Of the walks, he shook his head and said, "That's a feat."
The Angels won this one the way the A's had been doing it in recent days: jumping on the opposing starting pitcher right away.
Wells and Iannetta hit consecutive RBI singles in the second for Los Angeles, trying to gain ground on the A's in the wild card.
"When you play the team ahead of you, it's your best chance to make up ground," said Wells, who has never been to the postseason in parts of 14 major league seasons. "We know what's at stake. Right now, it's just a matter of if we do it collectively then we're going to win our share of ballgames. That's all that matters at this point."
Iannetta is batting .386 (22 for 57) with 12 RBIs over his last 16 games.
Scioscia said before the game he is unsure whether Jered Weaver (16-4) will be able to pitch Friday as planned back home against Detroit. Weaver was struck on the right arm by a line drive from Dustin Ackley's bat in the fifth inning of his loss Sunday at Seattle.
"Jered is a little tender where he got hit," Scioscia said. "We're going to wait and see how he's feeling."
Yet Weaver believes he will be ready.
"It's just a little bruise," Weaver said. "No worries."
The Angels are 4-3 at the Coliseum this season but trail the season series 7-6. ... Oakland recalled RHP Tyson Ross from Triple-A Sacramento and he will work out of the bullpen as an option for long relief. ... A's manager Bob Melvin said it "might be a long-shot" for the team to get INF Eric Sogard back from a high ankle sprain. He hurt the ankle while on a minor league rehab assignment after missing time with a strained back. ... Oakland's starters had their 8-0 streak over the previous eight games snapped. ... According to STATS LLC, the team played for the 13th time on Labor Day since 1961, tied for the most meetings on the holiday during that stretch. ... RHP Jarrod Parker (9-7) pitches Tuesday night's middle game for Oakland against Angels RHP Zack Greinke (3-2). ... Wells walked once all of last September.