The umpire stepped off the plate and opposing pitcher Lance McCullers then also delayed play to ensure the crowd's cheers for Piscotty continued.
Piscotty touched his heart on his jersey before hitting a single.
His father was in attendance and later congratulated his son while being interviewed on the video board.
"It was a special moment," Piscotty said. "I got in the box and heard the crowd start to roar and stepped out. I just wanted to acknowledge and to say thank you for all the support the A's community has given me. It was a cool moment and I know my mom was watching."
"All day, I didn't feel alone. I felt like someone was with me," Piscotty said a day later.
"I had a round in batting practice where I hit five homers out of five and I've never done that. That's not me."
The Astros went onto win the game 4-2.