Downs, who joined the Astros on Wednesday, was officially activated on Saturday before Houston's second of three games opposing the D-backs. The 26-year-old infielder was claimed off waivers from San Francisco on Aug. 25, and as a result of a league rule, needed to spend 10 days in the Minor Leagues prior to his promotion.
Downs, who put in extra work in the batting cages during his hiatus, said he would hope he gets opportunities to prove his mettle in the Astros' final 28 games.
"I'm obviously not going to come in and start and take a position over," he said. "I figure I'll go in late -- pinch-hit, pinch-run -- whatever they want me to do right now."
Manager Brad Mills said he, too, would like the chance to evaluate Downs, who he was impressed with in mid-May. Then a Giant, Downs went 1-for-9 (RBI double) in the clubs' three-game series and played error-free defense at second base.
"He looked really good against us," Mills said. "When [he'll play for us], I'm not exactly sure. How much, I don't know how much that will be available."