San Francisco, CA -- (Sports Network) - Jack Cust drove in two runs and the Athletics got the best of former teammate Barry Zito, beating the San Francisco Giants, 5-1, in the opener of a three-game series.

Zito (2-10), a three-time All-Star and the 2002 AL Cy Young award winner during his seven years with the A's, jumped ship to the Giants for a seven- year, $126 million deal, but things haven't worked out thus far. He's now 13-23 during his tenure with the Giants. The lefty allowed six hits and four runs over 5 2/3 innings on Friday.

Zito is 0-3 with a 9.21 ERA lifetime against the A's, walking 12 in 13 2/3 innings versus his former team.

Greg Smith and three relievers combined on the five-hitter. Smith (4-5) allowed three hits and a run, while walking a career-high six batters against four strikeouts in five innings to win for just the second time in his last nine starts. Chad Gaudin threw two innings, while Keith Foulke and Huston Street each threw a frame as the A's posted their seventh win in 11 games.

Daric Barton had two hits and an RBI for Oakland, while Mark Ellis stroked a pair of hits and scored twice.

Omar Vizquel stole home with the bases loaded to produce the only run for the Giants, who lost for the third time in four games.

It was an odd night at AT&T Park, Vizquel had the Giants' first straight steal of home since April 14, 1983 when Max Venable turned the trick in a game against the San Diego Padres. Also, Friday's game was interrupted for two minutes with two outs in the bottom of the ninth inning when the sprinkler system went off in the infield.

The Giants loaded the bases in the second inning. Vizquel then took advantage of Smith not looking behind him. As the left-hander got ready to throw a pitch to Jose Castillo, Vizquel took off and easily stole home. However, Castillo flied out to center to keep it a 1-0 contest.

"I'm glad it didn't make a difference in the game," A's manager Bob Geren said. "That's an unusual play. We were all yelling, but he flat out couldn't hear."

The A's then struck for three runs in the third. Barton singled, Ellis walked with one out and Ryan Sweeney, activated off the disabled list earlier in the day, singled up the middle to tie the game. Cust followed with a sacrifice fly to left, and Eric Chavez then doubled to left to extend the lead to 3-1.

The A's loaded the bases in the sixth and Zito walked Barton to force in a run. Vinnie Chulk then replaced Zito and fanned pinch-hitter Emil Brown to end the inning.

Ellis doubled leading off the seventh and scored on another Cust sacrifice fly.

Game Notes

Zito has walked 44 batters to just 38 strikeouts this year...The A's have won their last four games against the Giants and their last four at AT&T Park...Chavez hit his 270th career double, tying him Campy Campaneris for ninth in Athletics history...Smith got his first major league hit with a single in the fifth.