Arizona Diamondbacks vs San Francisco Giants Preview
Today's Starting Matchup
Today's starting pitching matchup features Arizona Diamondbacks's Merrill Kelly (4-3, 5.71 ERA) against San Francisco Giants's Landen Roupp (5-4, 3.27 ERA).
San Francisco Giants's Landen Roupp posts an solid 3.27 ERA this season, while Merrill Kelly has been struggling at 5.71. There is a clear gap in starting pitching quality.
Advanced metrics: Merrill Kelly — FIP 5.64, K% 14.9%, 41.0 IP / Landen Roupp — FIP 2.61, K% 27.2%, 55.0 IP
Team Season Comparison
2026 season record: Arizona Diamondbacks 28-24 (.538), San Francisco Giants 22-31 (.415).
Arizona Diamondbacks holds the edge in the season standings, though San Francisco Giants can't be counted out based on head-to-head matchups.
Recent form: Arizona Diamondbacks on a 2-game win streak, San Francisco Giants on a 2-game win streak.
Based on starting pitching, San Francisco Giants holds the edge.
Oracle Park is widely considered one of the most pitcher-friendly venues in baseball.
Bullpen Analysis
Arizona Diamondbacks bullpen: 13 relievers on the active roster. Key arms: Brandon Pfaadt 5.60 ERA, 27K in 35.1IP, Brandyn Garcia 1.17 ERA, 7K in 7.2IP, Eduardo Rodriguez 2.24 ERA, 43K in 60.1IP.
San Francisco Giants bullpen: 13 relievers on the active roster. Key arms: Adrian Houser 5.30 ERA, 31K in 52.2IP, Caleb Kilian 2.42 ERA, 25K in 22.1IP, Erik Miller (Setup) 3.77 ERA, 21K in 14.1IP.
Win Probability
Projected win probability: Arizona Diamondbacks 38% vs San Francisco Giants 62%
Factors: San Francisco Giants's starter owns the lower ERA, San Francisco Giants's home-field advantage. Of course, baseball's inherent randomness means actual results may differ.
Key Tactical Points
Workload comparison: Merrill Kelly averages 5.9 IP per start vs. Landen Roupp at 5.5 IP. Getting six-plus innings from the starter significantly eases the bullpen burden.
Oracle Park is classified as a pitcher-friendly park. Starter endurance becomes even more critical.