Austin Slater and Darin Ruf hit long homers and Anthony DeSclafani pitched 8 2/3 solid innings as the San Francisco Giants notched a 5-2 victory over the Arizona Diamondbacks on Sunday night in Phoenix.

The Giants lost seven-time All-Star catcher Buster Posey with a left thumb contusion in the sixth inning. X-rays were negative.

Ruf also had a run-scoring double in addition to his two-run shot as the Giants won their third straight game to conclude the four-game series and remained a half-game ahead of the Los Angeles Dodgers in the National League West.

DeSclafani (9-3) gave up two runs and six hits to win for the fifth time in his past six decisions. He struck out seven and walked two in a 107-pitch effort.

Christian Walker's RBI single ended DeSclafani's night and fellow right-hander Tyler Rogers entered. Rogers walked Pavin Smith in an 11-pitch at-bat before retiring Josh Reddick on a grounder to end it for his 10th save.

The Diamondbacks have dropped 50 of their past 58 games.

Posey scored twice and drove in one run before exiting.

The 34-year-old Posey was shaken up when a foul ball off the bat of Arizona's Daulton Varsho smacked off the thumb area of his glove. Posey was examined by a trainer and initially stayed in the game.

But after Varsho struck out on the following pitch for the inning's second out, Posey winced in pain. He looked over at the Giants' dugout, and signaled that he couldn't continue.

Curt Casali entered in place of Posey.

Slater's blast was his second long homer in two nights. He smacked one 463 feet in Saturday's game and topped it Sunday with a 467-foot missile in the third inning.

Arizona left-hander Caleb Smith (2-5) lost his fourth straight decision. He gave up five runs, five hits, one walk and struck out five.

The Giants got things started with two runs in the first inning. Posey delivered a two-out run-scoring single and scored on Ruf's double to center.

Slater led off the third inning by hammering a 1-1 changeup from Smith into the second level of seating in left center to make it 3-0. It is Slater's ninth blast of the campaign.

Posey drew a two-out walk in the top of the sixth before Ruf slugged a 1-2 curveball 439 feet over the fence in left. The homer is Ruf's seventh of the season.

Arizona got on the board in the bottom of the seventh when Asdrubal Cabrera hit a leadoff double and scored on Reddick's two-out single to center.

--Field Level Media