• The Diamondbacks are -135 favorites vs the Giants
• Giants vs Diamondbacks Over / Under today: 8.5 Runs
• Giants / Diamondbacks TV Channel: NSBA | DBTV

The San Francisco Giants (+110) visit Chase Field to take on the Arizona Diamondbacks (-135) on May 20, 2026. First pitch is scheduled for 3:40 pm in Phoenix, AZ.

This season, the Giants are 20-29 against the spread (ATS), while the Diamondbacks are 29-17 ATS.

Giants vs Diamondbacks Starting Pitchers Today:

• Giants starting pitcher: Tyler Mahle 1-5, 5.64 ERA
• Diamondbacks starting pitcher: Merrill Kelly 3-3, 5.86 ERA

Giants vs. Diamondbacks Odds, Run Line, Over/Under & Moneyline

Giants vs Diamondbacks Prediction for Today’s Game

Based on recent trends the model predicts the Diamondbacks will win Wednesday‘s MLB game with 54.9% confidence, factoring in game simulations, recent player performances, starting pitchers and injuries.

Bet now on Giants vs Diamondbacks and all games with BetMGM

We’ve highlighted some favorite MLB player prop bets for Giants players for Wednesday‘s game, looking at profitable historical betting trends:

Best Giants Player Prop Bets Today:

• Luis Arraez has hit the Home Runs Over in 2 of his last 5 games (+20.00 Units / 400% ROI)
• Harrison Bader has hit the Total Bases Over in 18 of his last 25 away games (+12.05 Units / 36% ROI)
• Matt Chapman has hit the Hits Under in 13 of his last 20 games (+10.15 Units / 50% ROI)
• Matt Chapman has hit the Runs Under in 13 of his last 15 games (+9.55 Units / 34% ROI)
• Casey Schmitt has hit the Singles Over in 17 of his last 25 away games (+9.50 Units / 36% ROI)

And here are some favorite MLB player prop bets for Diamondbacks players for Wednesday‘s game, looking at profitable historical betting trends:

Best Diamondbacks Player Prop Best Bets Today:

• Adrian Del Castillo has hit the Runs Under in 14 of his last 15 games at home (+12.15 Units / 44% ROI)
• Geraldo Perdomo has hit the Hits Under in 13 of his last 20 games (+9.40 Units / 38% ROI)
• Nolan Arenado has hit the Home Runs Over in 2 of his last 5 games at home (+9.30 Units / 186% ROI)
• Corbin Carroll has hit the RBIs Under in 19 of his last 25 games (+8.00 Units / 16% ROI)
• Geraldo Perdomo has hit the Singles Under in 14 of his last 20 games at home (+7.85 Units / 35% ROI)

Giants Best Bets Today:

• The San Francisco Giants have hit the Team Total Under in 23 of their last 35 away games (+9.40 Units / 23% ROI)
• The San Francisco Giants have hit the Game Total Under in 11 of their last 16 away games (+5.50 Units / 31% ROI)
• The San Francisco Giants have hit the 1st Five Innings (F5) Team Total Under in 29 of their last 50 games (+4.75 Units / 8% ROI)
• The San Francisco Giants have hit the Moneyline in 5 of their last 10 games (+2.65 Units / 26% ROI)
• The San Francisco Giants have hit the 1st Five Innings (F5) Moneyline in 4 of their last 8 games (+2.50 Units / 31% ROI)

Diamondbacks Best Bets Today:

• The Arizona Diamondbacks have hit the 1st Five Innings (F5) Team Total Under in 24 of their last 30 games at home (+17.15 Units / 47% ROI)
• The Arizona Diamondbacks have hit the Moneyline in 31 of their last 50 games at home (+10.50 Units / 17% ROI)
• The Arizona Diamondbacks have covered the Run Line in 30 of their last 50 games at home (+10.25 Units / 16% ROI)
• The Arizona Diamondbacks have hit the Team Total Over in 30 of their last 50 games at home (+9.05 Units / 16% ROI)
• The Arizona Diamondbacks have hit the 1st Five Innings (F5) Moneyline in 26 of their last 50 games at home (+9.00 Units / 14% ROI)

Giants Against the Spread (ATS) Record

Against the spread this season, the Giants are 20-28 against the Run Line (-19 Units / -26.78% ROI).

• 20-29 when betting on the Moneyline for -6.45 Units / -12.24% ROI
• 21-25 when betting on the total runs Over for -6.45 Units / -11.93% ROI
• 25-21 when betting on the total runs Under for +2 Units / 3.72% ROI

Diamondbacks Against the Spread (ATS) Record

Against the spread this season, the Diamondbacks are 29-17 against the Run Line (+7.5 Units / 11.35% ROI).

• 24-23 when betting on the Moneyline for +1.65 Units / 3.13% ROI
• 24-21 when betting on the total runs Over for +1 Units / 1.93% ROI
• 21-24 when betting on the total runs Under for -5.2 Units / -10.08% ROI

Diamondbacks vs Giants Home Run Prop Bets Today

Diamondbacks vs Giants Total Hits Prop Bets Today

Diamondbacks vs Giants Strikeout Prop Bets Today

Giants Keys to the Game vs. the Diamondbacks

The Giants are just 14-5 (.737) when leading entering the 7th inning this season — 2nd lowest in MLB; League Avg: .866.

The Giants are just 5-27 (.156) when scoring 4 or fewer runs this season — lowest in MLB; League Avg: .278.

The Giants are just 20-26 (.435) when allowing 5 or more extra base hits this season — tied for 2nd lowest in MLB; League Avg: .532.

The Giants are just 0-22 (.000) when trailing entering the 7th inning this season — tied for lowest in MLB; League Avg: .134.

Diamondbacks Keys to the Game vs. the Giants

The Diamondbacks are 5-15 (.250) when trailing entering the 7th inning this season — tied for 2nd best in MLB; League Avg: .134.

The Diamondbacks are just 78-21 (.788) when leading entering the 7th inning since the 2025 season — 2nd lowest in MLB; League Avg: .873.

The Diamondbacks are 7-84 (.077) when trailing entering the 9th inning since the 2025 season — 3rd best in MLB; League Avg: .045.

The Diamondbacks are just 86-15 (.851) when leading entering the 8th inning since the 2025 season — 2nd lowest in MLB; League Avg: .906.

Giants Hitting Stats & Trends

Giants hitters have drawn walks in 6% of their PA’s against RHP this season — lowest in MLB.

Giants hitters have an OBP of just .292 (1,808 PA’s) this season — lowest in MLB.

The Giants are hitting .356 against pitchers who have thrown at least 80 pitches in the game this season — best in MLB.

Giants hitters have drawn walks in 6% of their PA’s this season — lowest in MLB.

Diamondbacks Hitting Stats & Trends

The Diamondbacks are batting .278 against LHP this season — best in MLB.

Diamondbacks hitters have a swing rate of just 24% on the first pitch of at-bats this season — lowest in MLB.

Diamondbacks hitters have struck out in just 17% of their PA’s against LHP this season — best in MLB.

The Diamondbacks are batting .341 in lefty-lefty matchups this season — best in MLB.

Giants Pitching Stats & Trends

Giants pitchers have thrown at least two strikes in their first three pitches to 55% of opposing batters this season — lowest in MLB.

Giants pitchers have induced opposing hitters to ground into 48 double plays in 357 opportunities (13%) this season — best in MLB.

Opponents have a groundball rate of 47% against Giants pitchers this season — 2nd highest in MLB.

Giants pitchers have a strikeout rate of just 19% in late innings this season — 2nd lowest in MLB.

Diamondbacks Pitching Stats & Trends

Diamondbacks pitchers have walked 8% of batters this season — tied for 4th best in MLB.

Diamondbacks pitchers have walked 6% of batters when facing the leadoff batter in the inning this season — tied for 3rd best in MLB.

Opponents have a miss rate of just 23% against Diamondbacks pitchers this season — 5th lowest in MLB.

Diamondbacks pitchers have a strikeout rate of just 19% with runners in scoring position this season — 4th lowest in MLB.

More MLB Reading:

• Home Run Predictions Today
• Best NRFI Bets Today
• Strikeout Props Today
• MLB Starting Pitchers Today

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