Keaton Winn’s first trip to a major league ballpark also became the site of his first big league save.

Winn worked four solid innings of relief Tuesday night to help the San Francisco Giants to an 11-3 win over the St. Louis Cardinals.

Mike Yastrzemski and Patrick Bailey homered and Michael Conforto added four hits and three RBIs to pace a balanced attack.

The Giants have won five straight road games and six of their last eight games overall. San Francisco won the first two games of the three-game set and claimed just their third series in St. Louis in 10 tries since 2013.

Winn allowed one run on one hit in a 55-pitch effort.

San Francisco outfielder Mitch Haniger suffered a fractured right forearm after being hit by a pitch from Jack Flaherty in the third inning. Haniger drove in two runs in the Giants 4-2 win over St. Louis on Monday.

Haniger battled back from an oblique injury in spring training and was rounding into form.

St. Louis lost for the ninth time in the 11 games. The Cardinals fell to 27-41 overall, the team’s worst start sing opening the 1978 campaign 24-44.

Yastrzemski and Bailey hit back-to-back homers in the sixth to push the lead to 9-2.

Conforto, who went 4 for 6, had a two-run single in first and an RBI hit in the third. San Francisco is 18-4 this season when he drives in a run.

The Giants scored three times in the fifth and sixth to break the game open.

San Francisco’s Luke Jackson (1-0) picked up the win with an inning of scoreless relief. Starter Alex Cobb allowed two runs on five hits over four innings.

Flaherty (3-5) allowed six runs on 10 hits over 4 1/3 innings.

UP NEXT

RHP Anthony DeSclafani (4-6, 3.89) will face LHP Jordan Montgomery (3-7, 3.88) in the finale of the three-game set on Wednesday afternoon. Montgomery tossed six scoreless innings in his last outing, a 7-4 win over Cincinnati on Friday.