The game turned in a single inning. Arizona scored six times in the fourth to break open what had been a 1-1 contest, and the Cardinals never recovered. The Diamondbacks won 9-4 at Busch Stadium before 22,376 fans.
The fourth-inning burst was built on a series of extra-base hits. Ildemaro Vargas doubled to left, scoring Tommy Troy and Nolan Arenado to give Arizona a 3-1 lead. LuJames Groover then homered to left (388 feet), scoring Vargas to push it to 5-1. Ketel Marte followed with a solo home run to left center (416 feet) to make it 6-1. Vargas finished 1-for-4 with 2 RBI; Groover went 1-for-3 with a home run and 2 RBI; Marte was 2-for-5 with a home run and 1 RBI, carrying 13 home runs and 47 RBI on the season.
Arizona added two more in the seventh — Moreno scored on Troy's ground rule double, and Troy scored on Lourdes Gurriel's double to left — then Groover scored on Gabriel Moreno's sacrifice fly in the eighth to extend the lead to 9-2. Tommy Troy finished 2-for-5 with 2 runs scored and 2 RBI. The Cardinals managed two late runs in the ninth, including a home run to left by Jose Fermin (387 feet) and a run-scoring single by Blaze Jordan, but the deficit was too large.
Matthew Liberatore absorbed the loss, falling to 3-5. He allowed 6 runs on 8 hits over 5.1 innings, walking 2 and striking out 3 on 98 pitches, with a 5.56 ERA. Ryan Thompson earned the win for Arizona, his third of the season against one loss, tossing 2.0 innings and allowing 1 run on 2 hits with 2 strikeouts, carrying a 2.54 ERA.
For St. Louis, Blaze Jordan went 2-for-3 with 3 RBI, and Fermin scored three times in a 2-for-3 effort with a home run and 1 RBI. The loss dropped the Cardinals to 42-35. Arizona improved to 40-39 with the victory.