Harris, recalled from Triple-A Las Vegas earlier in the day, went 1-for-4 with a two-run double and a run in a win over the Angels on Tuesday.
The rookie made an instant impact in his first big-league action since May 22, plating Lawrence Butler and Zack Gelof with his sixth-inning two-bagger to extend the Athletics' lead to 6-1. Harris finished the first big-league stint of his career earlier this season in an 0-for-14 funk that included a massive 43.8-percent strikeout rate, so his ability to break the ice at the plate on his first night back was a particularly welcome sight.