Tommy La Stella went 3-for-6 with a home run and five RBIs to pace the San Francisco Giants to a 15-4 win over the host Chicago Cubs on Saturday afternoon.

Brandon Belt added a home run and three RBIs for San Francisco, which won its sixth game in a row. The Giants (92-50) will go for a three-game sweep over the Cubs (65-78) in the series finale Sunday afternoon.

Willson Contreras went 2-for-3 with two RBIs to lead Chicago at the plate. Ian Happ contributed a triple and an RBI for the Cubs, who have dropped three of their last four games.

Giants right-hander Kevin Gausman (14-5) added to his career high in victories. He allowed three runs on eight hits with nine strikeouts in six innings.

Cubs right-hander Zach Davies (6-11) remained winless since July 23. He was battered for five runs on four hits in two innings. He walked two and fanned one.

Chicago opened the scoring in the bottom of the first inning. Contreras hit an RBI single to right field to bring home Rafael Ortega.

San Francisco responded with five runs in the top of the second inning and never looked back. Davies got two outs in the inning before allowing a two-run double by La Stella, followed by a three-run shot by Belt for his 23rd homer of the season.

The Giants made it 6-1 in the third on an RBI single by Evan Longoria.

Happ ripped an RBI single in the bottom of the frame, and Contreras delivered another RBI single moments later to cut the deficit to 6-3.

A six-run fifth inning for San Francisco broke the score open to 12-3.

La Stella hit a three-run home run to right field. Mike Yastrzemski later hit a two-run single to right, and Longoria capped the big inning with a bases-loaded walk to score LaMonte Wade Jr.

Longoria notched his third RBI on a sacrifice fly in the eighth. The Giants loaded the bases again, which led to another run when Thairo Estrada drew a walk for his 21st RBI.

Wade increased the Giants' lead to 15-3 in the ninth with an RBI single.

Chicago capped the scoring on a sacrifice fly by Scott Effross.

--Field Level Media