Athletics at Arizona Diamondbacks: Prediction, Odds & Preview

The Athletics arrive at Chase Field on July 20 holding a 41-49 record and facing a Diamondbacks club that sits at 44-45 and carries the home-field advantage. The DiamondIQ model's estimate gives Arizona a 57.8% win probability against Oakland's 42.2%, a gap driven entirely by the difference in records and the home-field edge at Chase Field, as the model does not incorporate starting pitching into that figure. That distinction matters here, because both teams have yet to name a probable starter, leaving the pitching component of this matchup genuinely open.

With both starting pitching slots listed as TBD, the bullpen situations take on added weight, and neither side is particularly well-positioned heading in. Oakland's BullpenIQ sits at 57 out of 100, which is the stronger of the two marks, though six relievers are rated heavy from the prior three games and only one is fresh, with closer Hogan Harris available as the back-end option. Arizona's bullpen grades out at 53 out of 100, a more taxed unit with no fresh arms, four rated heavy, three likely unavailable entirely, and closer Paul Sewald as the anchor. The D-backs' relief depth looks thinner at this point, which could become a meaningful factor if the game extends deep without a defined starter in place.

Playing conditions at Chase Field will be extreme, with a forecast of 111 degrees Fahrenheit at first pitch, clear skies, zero percent precipitation, and a 14-mph west wind blowing left to right. That wind orientation can carry balls toward the right-field side and may elevate scoring opportunities for right-handed pull hitters in particular. On the injury front, Oakland is without Brent Rooker, Jacob Wilson, and Tyler Soderstrom, a significant loss across multiple lineup spots, while Arizona is missing Jordan Lawlar and carries several pitchers on the 60-day IL. The model leans Arizona, but the combination of unknown starters and a more depleted D-backs bullpen gives Oakland a pathway worth monitoring as lineups and any starter announcements emerge closer to first pitch.