Cincinnati Reds vs. Arizona Diamondbacks Prediction – August 21, 2026
The Cincinnati Reds head to Chase Field on August 21, 2026, to face the Arizona Diamondbacks in what the WP Baseball Predictor model projects as a notably lopsided contest. With Arizona holding a 62.0% win probability to Cincinnati's 38.0%, the Diamondbacks moneyline is the clear WP Pick heading into this matchup. Here's a full breakdown of why the model leans so heavily toward the home side.
Starting Pitcher Matchup: Rodriguez Holds a Clear Edge
The pitching matchup is the most compelling storyline of this game, and it strongly favors Arizona from the outset.
Nick Lodolo (Reds)
Nick Lodolo takes the mound for Cincinnati carrying an xFIP of 4.98, a figure that suggests he has been susceptible to regression and is not pitching at an elite level by predictive metrics. xFIP is a fielding-independent measure that normalizes home run rates, meaning Lodolo's underlying performance signals genuine vulnerability. Against an Arizona lineup that carries a team wOBA of .310, Lodolo faces a meaningful test.
Eduardo Rodriguez (Diamondbacks)
Eduardo Rodriguez presents a starkly different profile. His xFIP of 3.91 is comfortably in the above-average range and stands as a significant advantage over Lodolo's mark. That gap of over a full point in xFIP is not trivial — it reflects Rodriguez's ability to limit hard contact and control outcomes in a way that Cincinnati's starter simply has not matched. This pitching edge is one of the primary drivers behind the WP model's strong lean toward Arizona.
Why WP Baseball Predictor Favours the Diamondbacks
The model's 62.0% win probability for Arizona isn't built on pitching alone. When the team-level metrics are examined side by side, a consistent advantage emerges for the Diamondbacks across the board.
- Offense: Arizona's team wOBA of .310 edges out Cincinnati's .303, indicating a more productive and dangerous lineup overall.
- Pitching Staff: The Diamondbacks carry a team FIP of 4.46 and a team ERA of 4.18, both superior to the Reds' FIP of 4.73 and ERA of 4.47.
- Starting Pitcher Edge: Rodriguez's xFIP of 3.91 versus Lodolo's 4.98 represents the sharpest individual advantage in this matchup.
Across offense, rotation quality, and run prevention, Arizona holds the edge in every major category. The WP model correctly identifies this as a strong favourite situation for the home team.
Injury Report: Key Absences on Both Sides
Both rosters are managing notable absences heading into this contest, though the impact must be considered carefully.
Reds Injuries
- Julian Aguiar – Undisclosed (7-Day IL)
- Jose Franco – Forearm (7-Day IL)
- Garrett Hampson – Undisclosed (7-Day IL)
- Brandon Leibrandt – Undisclosed (7-Day IL)
- Tony Santillan – Oblique (15-Day IL)
Diamondbacks Injuries
- Yordin Chalas – Undisclosed (7-Day IL)
- Aramis Garcia – Undisclosed (7-Day IL)
- Lourdes Gurriel – Thigh (10-Day IL)
- Drey Jameson – Hip (15-Day IL)
- Ketel Marte – Knee (10-Day IL)
The loss of Ketel Marte is the most notable absence on the Arizona side, as he is one of the Diamondbacks' most consistent offensive contributors. Cincinnati's injury list is longer by volume, with five players sidelined, which further thins an already below-average roster.
Dark Horse Home Run Picks
Looking for value in the home run market? The WP model highlights two players worth targeting at elevated odds.
JJ Bleday – Reds
Despite Cincinnati's underdog status, Bleday offers intriguing power upside and is worth a speculative HR play at the right price.
Corbin Carroll – Diamondbacks
Carroll's combination of speed and pop makes him a legitimate HR threat at home, and with Arizona expected to generate offense against Lodolo, Carroll is the top dark horse pick of the night.
Final Prediction
The WP Baseball Predictor model points firmly to the Arizona Diamondbacks moneyline on August 21, 2026. Eduardo Rodriguez's pitching advantage, superior team-wide metrics, and home field support a 62.0% win probability that makes Arizona a worthy strong favourite in this contest.