St. Louis Cardinals vs Arizona Diamondbacks Prediction, Odds and Picks for Friday, 07/18/25

Winning the NL West may be out of reach for the Diamondbacks, but their playoff hopes are still alive. Arizona sits 5.5 games back of a wild-card spot, while the Cardinals remain firmly in the hunt — sitting 6.5 games out in the NL Central lead and 1.5 games out of wild-card position. On the mound for St. Louis will be Sonny Gray, who enters with a 9-3 record and a 3.50 ERA. For the Diamondbacks, Merrill Kelly will get the nod; he is 8-5 with a 3.34 ERA. 

The Diamondbacks’ offense hasn’t been the problem this season; it’s their bullpen, which has posted a 4.94 ERA that ranks fourth-worst in the majors. Offensively, the Diamondbacks sit fourth in the league in terms of runs scored, sitting at 5.1 runs per game. They have a .772 OPS. The Cardinals score 4.6 runs per contest and boast a .715 OPS. Both starters have been pitching well this year, but at the end of the day I have to side with the Cardinals. Gray has the slight edge over Kelly on the mound, but it’s Arizona’s bullpen that scares me. I have seen this Arizona bullpen blow too many games this season, and with the Cardinals having the stronger bullpen to close things out, I think that will be the big difference maker on Friday. Give me the Cardinals to get the job done, making them my best bet of the day. 

Cardinals vs Diamondbacks prediction: St. Louis ML (+100) available at time of publishing. Playable at that number.

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