Barry Zito threw seven strong innings and the San Francisco Giants beat the Cubs 6-3 on Tuesday night for a sweep of a day-night doubleheader.Zito (1-1) pitched for the first time since leaving his start on April 16 with a right foot sprain. He allowed four hits and two runs, leading the Giants to their seventh straight win.Brian Wilson got his 24th save.Nate Schierholtz had three hits and two RBI to pace the San Francisco offense, and Brandon Crawford added two hits and two RBI. Rodrigo Lopez (0-2) — pressed into starting duty after throwing out of the bullpen for most of the season — allowed eight hits and four runs in 4 2/3 innings for the Cubs.Pat Burrell and Aaron Rowand each drove in three runs as the Giants won the opener 13-7. In the second game, Lou Montanez hit a two-run homer for the Cubs, who were held to five hits. Aramis Ramirez also homered.Zito was sharp early, striking out Reed Johnson to start the game and retiring first six Cubs.Alfonso Soriano led off the third inning with a single. Montanez followed with his first Cubs homer — 11 years and 22 days after he was drafted by the team in the first round of the 2000 draft.Montanez had four big league homers during his time with the Orioles in 2008 and 2009, but he played 1,076 games in the minors after being selected by the Cubs. His blast to left put the Cubs up 2-1.Zito shut down the Cubs after Montanez’s homer for his longest outing since August 6, 2010.The Giants scored in the second when Cody Ross led off with a double and scored on Schierholtz’s single.Lopez struggled in the Giants’ five-run fifth.The first run had a controversial call. With Andres Torres on third, Pablo Sandoval hit a broken-bat fly into center. Johnson charged in to make the catch and with his momentum going toward the plate, he made a perfect throw to catcher Geovany Soto, who tagged the sliding Torres.Home plate umpire Tim McClelland initially called Torres out, but when the ball trickled out, the call was changed. Cubs manager Mike Quade charged onto the field, arguing that Soto held the ball long enough for the out. The umpires consulted at the mound, but the call wasn’t changed and the game was tied at 2.Lopez allowed back-to-back singles to Aubrey Huff and Ross, and was removed after throwing 96 pitches.Reliever John Grabow’s first pitch to Schierholtz was lined for a single, scoring Huff. Crawford doubled, scoring Ross and Schierholtz. Eli Whiteside singled in Crawford. The first four batters to face Grabow reached.In the first game, the Giants’ offense had season-best totals in runs (13) and hits (18) in a 13-7 win.Burrell and Rowand led the attack with three RBI apiece. Burrell had three hits and slammed his seventh homer, Miguel Tejada also had three hits and Rowand had a three-run double.Ryan Vogelsong (6-1) got the win despite allowing a season-high six runs — three earned — and matched his high for the season with four walks in five innings.Cubs starter Doug Davis (1-7) lasted just 4 1/3 innings, during which he gave up 12 hits and 10 runs.Carlos Pena hit a two-run homer, walked and scored two runs for the Cubs. Blake DeWitt had two singles and three RBI, and Koyie Hill added a solo homer.

NOTES—Mike Quade got a nice pregame surprise when it was announced that Giants manager Bruce Bochy had added him to the NL staff for the All-Star game, to be played July 12 in Phoenix. Quade replaced former Washington manager Jim Riggleman, who resigned last week. … The Cubs demoted rookie utility player DJ Lemahieu between games, sending him to Triple-A Iowa. They recalled reliever Marcos Mateo from Iowa to bolster a tired bullpen that worked 4 2/3 innings in Tuesday’s opener. … Tuesday’s doubleheader was the Cubs’ second of the season. They split a doubleheader at Wrigley against the Padres on April 20. Tuesday’s games marked the ninth split doubleheader in franchise history, all of them since 1968. …The game one ended a streak of winning six straight series openers.