(Photo credit: Joe Rondone/The Republic / USA TODAY NETWORK via Imagn Images)

Alek Thomas had three hits and scored twice, including the go-ahead run on a Geraldo Perdomo single in the seventh inning, and the Arizona Diamondbacks defeated the San Francisco Giants 4-2 in the opener of a four-game series on Monday in Phoenix.

After a two-run double by Tyler Fitzgerald drew the Giants even at 2-2 in the top of the seventh, the Diamondbacks pushed across the eventual difference-maker in the bottom of the inning against San Francisco ace Logan Webb. Thomas and Jose Herrera hit consecutive one-out singles before Perdomo's blooper over the head of shortstop Willy Adames.

The Giants appeared once again to tie the score in the eighth when Christian Koss launched a high drive toward the top of the left field fence. Diamondbacks left fielder Tim Tawa made a leaping effort and reached toward the top of the fence as a fan was extending a glove toward the hit. The ball went over Tawa's glove and into the fan's mitt.

The umpires initially ruled fan interference and called it the second out of the inning, but a replay review showed there was no contact between the gloves and Tawa's path at the ball was not impeded. However, it was also ruled that the ball would not have cleared the fence without the interference, and Koss was awarded just second base.

Diamondbacks reliever John Curtiss then struck out Rafael Devers -- his fourth straight whiff on an 0-for-4 night -- and Shelby Miller came on to fan Heliot Ramos to strand Koss and allow Arizona to retain its one-run lead.

Eugenio Suarez led off the bottom of the eighth with his 26th homer of the season, giving Miller an extra run of cushion for the ninth. The veteran then retired the side in order for his 10th save, ending Arizona's four-game losing streak.

The Diamondbacks scored the game's first run on a throwing error by Giants catcher Patrick Bailey on a Herrera sacrifice bunt in the third, scoring Thomas, who had doubled. Lourdes Gurriel Jr. hit a solo homer, his 11th, off Webb in the sixth.

Curtiss (1-0) got two outs and was credited with the win after Ryne Nelson held the Giants to two runs and five hits over 6 2/3 innings. Nelson struck out seven without issuing a walk.

Webb (7-6) was charged with three runs on seven hits in 6 1/3 innings. He walked one and fanned seven.

Fitzgerald collected two doubles and Dominic Smith had a double and a single for the Giants, who lost for the sixth time in their past seven games.

--Field Level Media