PHOENIX -- Arizona rookie Mike Bolsinger was better than he's ever been in his brief big league career. Unfortunately for the Diamondbacks, Madison Bumgarner was even better.
Bolsinger pitched five-hit ball into the eighth inning, but Bumgarner turned in a dominant performance to lead the San Francisco Giants to a 4-1 victory on Sunday.
When Bumgarner took the mound for the ninth, the only hit he had allowed was an infield single that easily could have been an out. The lanky left-hander allowed an unearned run and two hits in eight-plus innings.
"He is good and that is why he will probably be an All-Star again this year," Bolsinger said. "All I could do is really keep the team in the game. I tried to and we just caught Bumgarner on one of his good days."
Another infield hit ended Bumgarner's outstanding day. He struck out seven and walked two.
"You are just hoping that you can hang in there and get to a guy like Bumgarner," Diamondbacks manager Kirk Gibson said. "He was exceptional. Maybe the best I have ever seen him. It seemed like his cutter was excellent, he was throwing his fastball wherever he wanted to. His curveball was good and some changeups as well."
Arizona's Paul Goldschmidt called it "one of the better performances" he had ever seen.
Bolsinger (1-3), making his seventh appearance and sixth start, gave up a run and five hits. He struck out four and walked one.
The Diamondbacks, mired in last in the NL West virtually since opening day, have lost eight of 11.
Sergio Romo gave up Martin Prado's RBI single but got his second save in two nights and his 22nd in 26 opportunities overall.
Cody Ross got Arizona's first hit when he reached on a dribbler to the left of the mound in the second. Bumgarner went to his right to get the ball, slid, and then stood up and threw low to first baseman Joaquin Arias.
"I just tried to get to it as soon as I could," Bumgarner said. "I thought sliding and picking it up and standing up would be the quickest to do it. I didn't want to air-mail it to Arias over there. I kind of threw it in the dirt and gave him a tough hop to get. Nine times out of 10 he comes up with that."
San Francisco won two in a row against Arizona after losing six straight. It was the third victory in the last 12 games for the NL West-leading Giants, who play the next 10 at home.
San Francisco led 1-0 through eight innings. The run scored when Tyler Colvin doubled home Brandon Crawford from first in the fifth inning. Colvin was out trying to stretch it to a triple on a superb relay throw by shortstop Didi Gregorius.
The Giants added three more in the ninth, including Joe Panik's run-scoring double for his first career RBI in his first major league start. Buster Posey also doubled home a run and Crawford had an RBI single.
In the Arizona ninth, pinch-hitter Jordan Pacheco reached on an error by shortstop Crawford and Ender Inciarte singled off the glove of third baseman Pablo Sandoval. Bochy then pulled Bumgarner, who was trying for his third career complete game.
Romo came on and gave up Prado's hit, but Goldschmidt hit into a double play and Aaron Hill struck out to end it.
Arizona fell to 14-29 at home, including two season-opening losses to the Los Angeles Dodgers to open the season.
