Triggs (1-1) allowed three runs on four hits, walked none and struck out eight in six innings.
Jaime Garcia (10-10) gave up a three-run homer to Vogt with two out in the third and a two-run shot to Davis, his 34th, with two out in the first. Garcia has allowed seven homers in his past three starts after giving up six in his first 13 starts.
Matt Carpenter doubled twice, homered and scored the Cardinals' first three runs. His homer in the third extended the Cardinals' streak to 17 games with a homer, matching their season best.
Ryon Healy doubled in the third to extend his hitting streak to 14 games, the longest active streak in the majors.
The Cardinals finished interleague play 1-8 at home and 8-12 overall. Oakland finished 7-13.
Vogt, in full catcher's gear, and Cardinals backup OF Tommy Pham delivered the lineup cards to the umpires before first pitch.
Athletics: INF Billy Butler (concussion) is expected to be cleared to return Monday.
Cardinals: SS Aledmys Diaz (right thumb) will see a hand specialist Monday to determine when he could return. Diaz has not played since July 31.
Athletics: Rookie LHP Sean Manaea (5-8, 4.53) starts the opener of a three-game series at Houston seeking his first road win. He worked seven scoreless innings against the Astros in a 2-1 loss July 10.
Cardinals: RHP Carlos Martinez (12-7, 3.13) will make his third start at Milwaukee as St. Louis opens a nine-game, three-city trip. Martinez won his first two starts against the Brewers, allowing one run in 13 innings.