HOUSTON - The Houston Astros have optioned relief pitcher Ken Giles to Class AAA Fresno, the team announced Wednesday.

On Tuesday night against the Oakland Athletics, Giles entered the game in the 9th inning with Houston leading 4-0. He was taken out of the game after allowing three singles, including an RBI single, cutting into the Astros' lead, 4-1.

Related: Astros get wild walk-off win against Athletics

The Athletics tied the game at 4 in the 9th inning. A wild walk-off by Alex Bregman in the bottom of the 11th secured the 6-5 win for Houston.

Giles has a 4.99 ERA this season with 12 saves and 31 strikeouts in 34 games.