San Francisco, CA (Sports Network) - Rich Aurilia drilled a three-run homer to lift the San Francisco Giants to an 8-3 win and a split of a four-game series with the Chicago Cubs.

Aaron Rowand went 2-for-4 with two runs scored while Jose Castillo went 2- for-3 with an RBI and two runs scored for the Giants, who have won four of six overall.

Tim Lincecum (10-1) continued his stellar season and won his sixth straight decision, giving up three runs on seven hits in six innings of work. His last and only loss of the season occurred on April 29 against Colorado, a span of 13 starts.

Mark DeRosa drove in a pair of runs while Sean Gallagher (3-4) lost his third straight decision, giving up four runs -- three earned -- on four hits in five innings of work for the Cubs, who have dropped six of their last eight games.

"The last three series, beginning with Baltimore, we have not pitched very well at all," said Chicago manager Lou Piniella. "We've given up some runs. Maybe it was a result of Zambrano's absence. We'll see."

The Cubs got on the board in the first inning as Reed Johnson led off with a double and later came home on a Derrek Lee single.

However, the Giants answered with four runs in the second. Rowand led off with a single and moved to second on John Bowker's groundout. Castillo followed with a double to plate Rowand and later came home as Lincecum helped his cause with an RBI single. Fred Lewis then hit a triple to the gap in left-center to score Lincecum. Ray Durham then reached base on an error by Geovany Soto and Lewis came home for a 4-1 lead.

Chicago was able to get men on base over the next three innings, but were unable to bring any home.

However, the Cubs made it a one-run game in the sixth. Lee led off with a double and later moved to third on Jim Edmonds' single. After Soto struck out, DeRosa punched a double to left-center to bring home both runners and make it a 4-3 contest.

San Francisco, though, solidified its lead in the seventh as Aurilia delivered a pinch-hit, three-run home run for a 7-3 advantage.

The Giants tacked on another run in the eighth on an RBI single from Omar Vizquel for an 8-3 advantage.

Sergio Romo retired the Cubs in order in the eighth inning while Osiris Matos repeated the feat in the ninth to finish the game.