SAN FRANCISCO -- Rookie right-hander Chris Heston pitched his third straight gem, shortstop Brandon Crawford hit a two-run homer, and the San Francisco Giants ended their eight-game losing streak with a 4-1 victory Saturday night against the Arizona Diamondbacks at AT&T Park.

The Giants received their 2014 World Series championship rings during a ceremony before the game. Then they went out and played more like the team that has won three World Series in the past five seasons.

Heston (2-1) allowed one run on five hits over 7 2/3 innings. He walked one struck out six and beat the Diamondbacks for the second time this season. He earned his first major-league victory on April 8 at Chase Field, giving up two runs on three hits over six innings in a 5-2 Giants win against Arizona. He gave up just two runs (one earned) over seven innings in his second start but took the loss as the Giants fell 2-0 to Colorado.

Heston, who replaced the injured Matt Cain in the rotation, has a 0.87 ERA over three starts and 20 2/3 innings.

Giants left fielder Nori Aoki went 2-for-5 with a double and scored a run. Second baseman Joe Panik went 3-for-5 and scored a run, and catcher Buster Posey went 2-for-4 with an RBI.

Arizona right-hander Rubby De La Rosa (1-2) gave up three runs (two earned) and eight hits over 6 2/3 innings, taking his first loss of the season. He struck out seven

Left fielder David Peralta hit a solo home run for the Diamondbacks. Right fielder went 2-for-4, and first baseman Paul Goldschmidt had a double in four at-bats.

The Giants took a 1-0 lead in the first inning. Aoki smoked a leadoff double down the left-field line, and Panik brought him home with a single to left.

San Francisco made it 2-0 in the third as Panik singled with one out, moved to second on a passed ball and scored on Posey's broken-bat single to left with two outs.

Peralta led off the fourth inning with a home run into the right-field seats, cutting the Giants' lead to 2-1. Heston fell behind 2-0, and Peralta launched his 88 mph sinker on the inside corner for his second home run of the season.

Crawford answered with his third home run of the season, a two-run shot in the bottom of the fourth off De La Rosa, increasing the Giants' lead to 4-1. Right fielder Gregor Blanco lined a single with one out, and Crawford hit De La Rosa's first-pitch changeup into the right-center-field seats.

NOTES: Giants RHP Jake Peavy was placed on the 15-day disabled list with a strained back. He said an MRI on Saturday revealed a muscle strain caused by a misaligned disk in his lower back. "I've got some issues I've got to get right," Peavy said. "It hasn't been a problem in the past. I hope it will heal fast." Peavy said surgery has not been mentioned as an option. He'll have complete rest for an undetermined length of time. The Giants have an off day Monday, and manager Bruce Bochy said he will skip Peavy's next turn in the rotation. ... The Giants recalled C Andrew Susac from Triple-A Sacramento. He was batting .350 (7-for-20) with three doubles and one RBI in six games. ... The Giants received their 2014 World Series rings during a pregame ceremony on the field at AT&T Park. Giants Hall of Famers Willie Mays, Willie McCovey, Orlando Cepeda, Juan Marichal and Gaylord Perry took part and received rings. ... The Diamondbacks were in their dugout when the Giants received their rings "to show our respect," manager Chip Hale said. "(Winning the World Series is) not easy to do and it's something that everybody, when we start the season, is aiming for. So hats off to them."