Their win Saturday night ended the Giants' stretch of nine-straight losses against Arizona and eight straight at Chase Field.
Sunday's rubber match marks a battle of veteran left-handers who have gone through a bit of a renaissance this season. Barry Zito takes the mound for San Francisco with a 2.21 ERA, and he's opposed by Joe Saunders, who sports a 2.50 mark.
But Saunders (2-2) struggled a bit in his last time out against the Cardinals. In 3 1/3 innings, he allowed three homers. The six earned runs he surrendered were more than the five he allowed in his previous five outings combined.
The loss Saunders took was part of a stretch that has seen the D-backs lose eight of their last 11 games. They trail the Giants by a game and a half for second place in the NL West. The Dodgers have pulled ahead early in the division race by six games over San Francisco.
But despite his team's recent struggles, D-backs manager Kirk Gibson has been impressed with the way the clubhouse has remained loose. The club has a stuffed animal called Lucky Henry by Gerardo Parra that's been in the clubhouse and dugout lately.
In other words, they are not letting their inconsistent play get them down.
"Through the whole ordeal, they have been great," Gibson said. "They have fun and they've stayed loose and stayed together. They live, the locker room lives together. It has not been irritable, they are working together."
Like Saunders, Zito is coming off his worst start as well, as the three earned runs he allowed in Los Angeles were a season high. But the fact that three earned runs is a season high for Zito speaks volumes about his improvement this season.
Giants: Belt to 2-hole
First baseman Brandon Belt batted second in the lineup on Saturday because manager Bruce Bochy said he wanted a more patient hitter there.
He went 1-for-5, but knocked in a run and scored a run in the Giants' win.
"He's a pretty disciplined hitter, so I think it'll be good," Bochy said of Belt, with 10 walks in 75 plate appearances. "I think any time you try to get some rallies going, you want to get someone who has good discipline, who can get you a walk and get on base."
Shortstop Brandon Crawford committed his eighth error on Saturday, an unsettling trend for San Francisco, as Crawford is in the starting lineup primarily for his glove.
"He knows what his job is and that's to play shortstop," Bochy said before Saturday's game. "We know there are going to be ups and downs, but we have to catch the ball better. It is concerning because it has been going on too long."
D-backs: Drew slides for first time
Recovering D-backs shortstop Stephen Drew slid for the first time since breaking his ankle last July. Drew slid six times on a mat and three times on the field, noting that he felt fine afterward.
"It felt normal so that's a good thing," he said. "Things have been going really good. I have had not had a really major setback and that's a good thing."
Drew said the next step is playing in consecutive games and sliding in a game. He also wants "to build up innings."
"It's been a long road," Drew said. "But hopefully, I'll be out there pretty soon."
Jason Kubel has hit safely in 12 of his last 13 games at Chase Field, batting .340 in home games during that stretch.
The D-backs are just 1-13 in games in which they score three or fewer runs.
Saunders has never beaten the Giants in his career, going 0-3 in four starts with a 4.15 ERA.
D-backs shortstop Willie Bloomquist has two homers, 10 hits and six RBIs in his 37 career at-bats against Zito. All those numbers are tops for the club against Zito.