San Francisco Giants vs Arizona Diamondbacks Prediction, Odds and Picks for Today, 05/19/26

The San Francisco Giants look for revenge in the second game of this series in the Valley of the Sun after falling 12-2 on Monday night. The 12 runs allowed were the most yielded on the road this season, and the second-most at any venue. The Over has cashed in three straight games for the Giants, averaging 6.0 runs per game (RPG) on offense in that 3-game span, while allowing 5.7 RPG. The Giants have allowed 4 or more runs in 5 of the past 6 outings. San Francisco turns to RHP Landen Roupp (5-4, 3.49 ERA, 1.14 WHIP) to get it back into the win column. However, he has really struggled in three May outings, going 0-3 with a 5.93 ERA, including 8 runs allowed in 9.2 IP across a pair of road starts.

The Diamondbacks have piled up 20 runs in the past 2 games, and 8 or more runs in 3 of the past 4 outings. Of course, 3 of those games were on the road at Coors Field, so that always helps bump up the numbers. The Over is 4-2 in the past 6 games, however, as the offense is back. The Snakes turn to RHP Ryne Nelson (1-3, 5.40 ERA, 1.16 WHIP), and he has been very giving this season. At home, he is 0-2 with a 9.18 ERA across 4 outings, allowing 17 runs in just 16.2 IP with 5 homers served up, and teams are hitting .282 against him as well. With Roupp struggling in May, and Nelson terrible for most of the season, let’s go with the over on Tuesday.

Giants vs Diamondbacks prediction: Over 8.5 (-120) at time of publishing. Playable to 9.5.

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