With the Giants and Royals tied at 2 in the third inning and Lorenzo Cain at first, Eric Hosmer hit a bullet to Panik's right.
"The ball shot through and I just told myself to just knock it down and try to get one out of it," Panik said.
Panik dove, gloved the ball, and while on his stomach, flipped it from his glove to shortstop Brandon Crawford, who threw to first to get Hosmer. Initially, Hosmer was ruled safe, but the play was overturned on a replay review.
"I would have never thought to get two," Panik said.
Nor did he ever think he'd be flipping the ball from his glove while laying on his stomach to start a double play.
"This is the first time I've ever done something like that," Panik said. "It was just instinctual. I couldn't get my bare hand to my glove."
Billy Butler grounded out to end the inning and the Royals, after scoring a pair of runs in the second inning, were unable to keep that momentum going in the third, thanks to Panik's play.
"That was the key to the game," said left-hander Jeremy Affeldt, who was on the mound at the time. "It kept them from rallying for another inning. So I think being able to shut it down real quick allowed me to go out for another inning. That was a big deal. For me, that was the biggest play of the night."
From behind home plate, catcher Buster Posey marveled at the play.
"That's a game-changer," Posey said. "That play he made on Hosmer was a game-changer. No doubt."
The play did come with a cost, though, as Panik quickly ran to the dugout while the replay review was going on to grab a new belt.
"I broke the buckle on that," Panik said. "It was pretty funny. That's the first time it's ever happened."
Showing poise under pressure -- not panicking if you will -- has become something the Giants expect out of Panik, despite the fact that he did not make his big league debut until May 22 this year and wasn't in the Majors for good until late June.
Panik filled a big hole for the team after expected starter Marco Scutaro was never fully healthy. Panik ended up hitting .305 while also playing stellar defense.
"He hasn't looked like a rookie this season," Crawford said. "He's been such a big part of this team and played such a solid game all the way around."
Wednesday night, he stood in the clubhouse with his teammates celebrating all around him and tried to take in all that had happened. That proved harder to do than making plays on the field.
"No, it hasn't sunk in yet," Panik said. "But I'll tell you what, it was an unbelievable game and atmosphere. You always want to call yourself a world champ and it's just special to be in this clubhouse and see World Series champions. It's what you always want to do and be, and four months into your rookie year, it's pretty crazy."