Petit became the fourth player in Pacific Coast League history -- and the second in 81 years -- to hit two grand slams in the same game as the Oklahoma City RedHawks rallied for a 10-5 triumph over the New Orleans Zephyrs.
Petit was pretty sure he was on his way to a miserable night when he misplayed Scott Cousins' two-out grounder in the second inning. Gookie Dawkins hit the next pitch from RedHawks starter Guillermo Moscoso over the center-field fence to give New Orleans a 2-0 lead.
The Zephyrs tacked on three runs in the third to make it 5-0.
"I was really upset about that. I wanted the game to be over really quick, especially after they scored five runs," Petit said. "I thought, 'This game needs to be over right now.' But it turned around the best way for me and my teammates."
The 25-year-old shortstop had not hit a grand slam in 2,794 Minor League at-bats before coming to the plate with the bases loaded in the fifth.
"I was thinking, 'Please hit the ball, get an RBI, just one, at least. Hit it hard,'" Petit said.
He greeted reliever Jay Buente by depositing an 0-1 pitch over the left-field fence for his fourth homer of the season and second in three games.
"He threw me a split and another split. I just tried to put a good swing on it," Petit said. "I guess I put a better swing on it than I thought."
The blast capped a five-run outburst and lifted Oklahoma City into a 5-5 tie. The game was still deadlocked in the eighth when the RedHawks loaded the bases on a walk by Jarrod Saltalamacchia, a single by Chad Tracy and an error.
"It was a 5-5 game and I said, 'C'mon, just get a base hit or a fly ball. All we need is one run to get the lead,'" Petit said.
The Venezuela native jumped on Brett Sinkbeil's first pitch, a slider, and lined it over the fence in left-center.
"I never thought it was gonna get out," said Petit, who realized when he reached first base that the ball had cleared the fence.
"I just started smiling, I didn't know what to do. I saw all my teammates laughing and smiling for me, too."
Petit joined Vernon's Pete Schneider (May 11, 1923), San Francisco's Babe Pinelli (July 4, 1929) and Salt Lake's A.J. Pierzynski (Aug. 10, 2000) as the only Pacific Coast Leaguers with two grand slams in one game.
"It's something I'm going to tell my family and friends, and we're going to celebrate," said Petit, who played 25 big league games over two seasons with the Athletics. "I'm just going to enjoy as much as I can but keep it away from my head. I don't want to change my swing or try to do too much."