July 21, 2025 3:39 AM EST

Houston Astros vs Arizona Diamondbacks 7/21/2025

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The Arizona Diamondbacks are 23-25 at home this season and are heavy favorites to beat the Houston Astros who are 23-21 on the road this season. The Diamondbacks have a better than 60% chance of winning based on 10,000 game simulations generated one play at a time by the AccuScore Simulation Supercomputer. Diamondbacks starter Zac Gallen is forecasted to have a better game than Astros starter Colton Gordon. Zac Gallen has a 52% chance of having a Quality Start (QS) while Colton Gordon has a 26% chance of a QS. If Zac Gallen has a quality start the Diamondbacks has a 85% chance of winning. His simulated strikeout to walk ratio is 3.4 and he has a 28% chance of having a 5 to 1 K/BB ratio. When he has a 5/1 ratio the Diamondbacks win 68%. In Colton Gordon quality starts the Astros win 62%. He has a 38% chance of having a 5 to 1 K/BB ratio and if he does his team wins 62% of simulations. In simulations we tracked the batter for each team that was most productive based his average hits, walks and RBI per simulation. The most productive batter for the Arizona Diamondbacks is Ketel Marte who averaged 2.79 hits+walks+RBI. He has a 50% chance of having a big game with 3+ Hits, Walks, RBI and if he has a big game the Diamondbacks have a 76% chance of winning. The most productive batter for the Houston Astros is Isaac Paredes who averaged 2.08 hits+walks+RBI. He has a 34% chance of having a big game with 3+ Hits, Walks, RBI and if he has a big game the Astros have a 48% chance of winning.

CURRENT SEASON: We advise relying on these trends after the first 6 to 8 weeks of the season. UNITS EDGE FAVORS: Houston Astros

Houston AstrosRECORDArizona DiamondbacksRECORDUNITS EDGE
Record on the Road23-21, 52% -16Record at Home23-25, 48% -770Houston Astros
VS Arizona Diamondbacks0-0 No GamesVS Houston Astros0-0 No GamesN/A
vs Team Under .50027-16, 63% 412vs Team .500 or Better25-28, 47% -462Houston Astros
Record As Road Underdog9-10, 47% 152Record As Home Favorite17-22, 44% -1117Houston Astros
When Colton Gordon Starts5-2, 71% 322When Zac Gallen Starts8-11, 42% -365Houston Astros

PAST 30 DAYS: We advise incorporating these trends along with the current Season after the first 6 to 8 weeks. UNITS EDGE FAVORS: Houston Astros

Houston AstrosRECORDArizona DiamondbacksRECORDUNITS EDGE
Record on the Road6-2, 75% 414Record at Home3-7, 30% -430Houston Astros
VS Arizona Diamondbacks0-0 No GamesVS Houston Astros0-0 No GamesN/A
vs Team Under .5002-1, 67% 1vs Team .500 or Better0-3, 0% -300Houston Astros
Record As Road Underdog3-1, 75% 332Record As Home Favorite2-6, 25% -458Houston Astros
When Colton Gordon Starts3-0, 100% 358When Zac Gallen Starts1-1, 50% -27Houston Astros

OVER-UNDER TRENDS

Houston AstrosRECORDArizona DiamondbacksRECORDO-U EDGE
OVER-UNDER ON ROAD19-21, 48% OverOVER-UNDER AT HOME25-21, 54% OverOVER
ROAD OVER-UNDER PAST 30 DAYS5-2, 71% OverROAD OVER-UNDER PAST 30 DAYS7-3, 70% OverOVER
ROAD OVER-UNDER LAST SEASON29-48, 38% OverROAD OVER-UNDER LAST SEASON50-29, 63% OverOVER
OVER-UNDER IN Colton Gordon STARTS2-3, 40% OverOVER-UNDER IN Zac Gallen STARTS11-8, 58% OverN/A

ACCUSCORE ADVISOR: AccuScore simulates every game thousands of times one play at a time. We are the industry standard in sports forecasting and the only company to be paid for sports picks and predictions by the biggest sports companies in the world. Our newest product, the AccuScore Advisor, provides Side Value, Money Line and Over-Under picks for every MLB game and rates them as One, Two, Three or Four Star picks. Three and Four Star picks have delivered over +10,000 units of profit the past 2 seasons. Visit AccuScore.com to find out what AccuScore\'s Advisor recommends for this game. The following trends are AccuScore\'s RIGHT-WRONG records and units (+/-) when making picks involving these teams.

SIDE VALUE (Current Season) - Houston Astros Road Games: 19-25, 43% -646 Arizona Diamondbacks Home Games: 21-27, 44% -1027 SIDE VALUE (PAST 30 DAYS) - Houston Astros Road Games: 2-6, 25% -359 Arizona Diamondbacks Home Games: 3-7, 30% -430

MONEY LINE (Current Season) - Houston Astros Road Games: 23-21, 52% -238 Arizona Diamondbacks Home Games: 22-26, 46% -960 MONEY LINE (PAST 30 DAYS) - Houston Astros Road Games: 2-6, 25% -479 Arizona Diamondbacks Home Games: 3-7, 30% -430

OVER-UNDER RECORD (Current Season) - Houston Astros Road Games: 16-17, 48% -270 Arizona Diamondbacks Home Games: 20-20, 50% -200 OVER-UNDER RECORD (PAST 30 DAYS) - Houston Astros Road Games: 2-4, 33% -240 Arizona Diamondbacks Home Games: 3-6, 33% -360

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