Porter came out to discuss the call with first-base umpire Paul Emmel, eventually issuing an official challenge on the call.
After two minutes and 37 seconds, the call was overturned, as Keuchel's foot was deemed to have touched the bag before Crisp. The out ended the inning with Oakland then up, 2-1.
Porter is 3-for-4 on challenges in the first year of MLB's expanded replay system.
The Astros even carried a little momentum from winning the challenge, as Chris Carter handed Houston the lead in the bottom of the frame with a two-run homer off Dan Straily.
Chris Abshire is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.