Abreu and Napoli each hit two-run home runs, leading the Angels to a 7-4 victory over the Oakland Athletics on Sunday, avoiding their first sweep by the A's in six years.
"This is the offensive day we've been looking for in quite some time," Angels' manager Mike Scioscia said. "It was a good day to get it."
Ervin Santana (15-9) gave up three runs and six hits to improve to 7-2 over his last nine starts. He walked four and struck out three.
"I know in years past I haven't gotten run support," Santana said. "I know the guys are trying to score. Maybe this is the year there's a lot of run support for me. When you score first, it's fun to pitch. It allows you to pitch better without adding too much pressure."
Vin Mazzaro (6-8) lost his sixth straight decision after allowing five runs on six hits over 4 1/3 innings. He walked three and did not strike out a batter. Mazzaro, who pitched with a blister according to Powell, has given up 12 earned runs over his last eight innings and hasn't won since July 24 against the Chicago White Sox.
"He really hasn't thrown the game that well in the last month or so," A's manager Bob Geren said. "The overall command of the strike zone is not where it needs to be."
Santana completed at least six innings for the 12th time in his last 14 starts and has been remarkably efficient since starting the season 1-3. He has recorded a decision in 21 of his last 22 starts.
"He went out there and made good pitches," Scioscia said. "We got six strong innings and that was good enough. He's been very consistent and we always feel good with him on the mound."
Santana has a career 1.80 ERA against the A's and improved to 12-3 against them in 21 appearances, 19 starts.
"It's just being in the strike zone, working ahead and working quickly," Santana said. "Throwing fewer pitches allows you to go deeper into the game."
Abreu hit a two-run home run in the third to put the Angels ahead. He entered the at-bat with two hits in his previous 34 at-bats. Abreu later walked and scored and singled home a run in the seventh.
"I need to make better pitches," Mazzaro said. "I fell behind a lot and it hurt me. The only way that's going to stop is to keep attacking the zone and getting ahead."
Napoli also hit a two-run shot in the third to give the Angels a 4-0 advantage.
"Mike got jammed a little bit on that ball and still got it out," Scioscia said.
Rajai Davis walked to open the third and stole his career-high 42nd base. He scored when Powell singled.
Hunter doubled home a run in the fifth and RBI singles from Abreu and Matsui in the seventh iced the game.
Cust singled in a run with two outs in the ninth. Ellis followed with a single before Fernando Rodney retired Larish to end the game.
A's Breast Cancer Awareness Day raised $70,650. ... A's IF Kevin Kouzmanoff left the game in the fifth inning with lower back spasms. ... The Angels scored more runs than they had in their previous four games combined. ... Angels RHP Dan Haren will make his first start against the Cleveland Indians in three years and the seventh overall. ... Abreu has six home runs against the A's this year. ... Santana matched Dean Chance for 10th on the Angels' all-time win list with his 74th victory.