OAKLAND, Calif. -- Jack Cust's patience and penchant for power kept him from making a single out.
"Any time you're not heading straight back to the dugout you have to feel good," Cust said. "I've been able to lay off close pitches and get myself into good hitter's counts. I've been able to make last-minute adjustments with the ball on its way and that means you're seeing the ball longer."
Cust hit two home runs and drew three walks in a game for the first time in his career. Kurt Suzuki, who agreed to terms on a four-year deal with the A's Friday, added a homer of his own and helped the A's win for the eighth time in 10 games.
Daric Barton also drove in two runs, and Kevin Kouzmanoff doubled twice and drove in a run.
Freddy Garcia (9-4) lasted a career-low 1 1/3 innings and had his personal six-game winning streak snapped. He gave up five runs on six hits, walking three and striking out two as the White Sox lost for the fifth time in 17 games.
"He ran into trouble from the beginning," White Sox manager Ozzie Guillen said. "Freddy has been great for us all year long. He was around the plate; he just got hit. I'll take that from him and move on."
Vin Mazzaro (6-2) gave up Ramon Castro's two-run homer in the second. He allowed three hits over six innings, walking three and striking out five.
"Young players usually get better and that's the case with Mazzaro," A's manager Bob Geren said. "He has better command of his pitches, his walks are down and his strikeout ratio is up. He got into trouble early and did a nice job of settling down."
Mazzaro, who won his fourth straight decision, retired 14 of his final 16 batters, and did not allow a hit after Castro's home run.
"I kept pounding the zone," Mazzaro said. "You can't be afraid to throw any of your pitches. My slider started working after that and I went from there. I'm definitely doing a better job of damage control."
Garcia needed a fine running catch by left fielder Juan Pierre to get out of a first-inning, bases-loaded jam. The first four A's hitters reached base safely against the right-hander.
Coco Crisp walked, stole second and scored on Barton's double. Suzuki singled and Cust walked before Garcia struck out Kouzmanoff and Ellis and nearly avoided further damage when Gross' foul pop landed safely between Omar Vizquel and Alexei Ramirez before driving in a run with an infield single.
"I started off with a walk and that's not the right foot to start on," Garcia said. "That was a lot of pitches for the first inning and I couldn't get anybody out. There's nothing you can do when you don't have it."
Castro's homer tied the game but the A's scored three times in the second on RBI hits by Barton, Suzuki and Kouzmanoff.
Suzuki and Cust homered in consecutive at bats leading off the fourth against Tony Pena. Cust added his second homer against Scott Linebrink in the eighth.
Cust started the season in the minor leagues and then hit two homers over his first 42 games following his May 15 call-up. He's hit six in his last 10 games and is three away from 100 in his career.
"He's in a zone," Mazzaro said. "He's swinging it well and seeing the ball. It's nice to get the run support."
Brad Ziegler threw two scoreless innings and Ross Wolf pitched a perfect ninth to complete the combined four-hitter.
The A's improved to an AL-best 23-10 in day games. ... The White Sox had won 11 of their last 12 day games. ... Chicago OF Alex Rios went 1 for 2 and improved his AL-best day batting average to .434 (43-99). ... Garcia also had an eight-game winning streak against AL West teams stopped. ... Gross ended an 0 for 16 streak with his infield single in the first. ... A's RHP Ben Sheets was placed on the 15-day DL before the game with a strained right elbow. The A's recalled Cedrick Bowers to replace Sheets.