ST. PETERSBURG -- Over the past three months, most players looked for ways to continue working on their craft and stay ready for the upcoming season. Apparently, Ji-Man Choi had enough extra time to become a switch-hitter.

With Blue Jays left-hander Anthony Kay on the mound, Choi stepped to the plate at Tropicana Field in the fourth inning. But the difference was that Choi, who had hit left-handed in all of his 735 MLB plate appearances prior to Sunday's 6-5, extra-inning win, stepped into the batter’s box as a right-handed hitter.

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In his first at-bat as a righty, Choi took two vicious swings but eventually struck out against Kay. In the sixth inning, however, Choi went full switch-hitter, smacking a 429-foot home run to left-center off of Kay to send the home dugout into a frenzy. The exit velocity on the home run was 109.1 mph, according to Statcast, the Rays’ hardest-hit ball of the season.

“The first at-bat as a righty, we were playing defense for quite a while, so I wasn’t really warmed up,” Choi said through interpreter Steve Nam. “The second at-bat came up, I just swung and the ball just traveled past the fence.”

Over the past few years, Choi typically starts his first batting-practice round with swings from the right side before switching over to his natural, left-handed swing. During Summer Camp, Choi took some at-bats from the right side, but quickly said he was just doing it because he was having fun.

Rays manager Kevin Cash added that he didn’t think Choi would hit from the right side in a game. Before the Blue Jays finale, Cash said he guessed that Choi was going to try hitting right-handed. Well, Choi did, and the result was unbelievable.

“I didn’t want to ask him, didn’t want to persuade him one way or the other, just wanted it to be his choice,” Cash said. “That’s pretty impressive to be able to do that. Switch-hit and then not do it for five years, other than kind of goofing around in the cage, and then he comes off against a good Major League pitcher and hits the ball into the deepest part of the ballpark.”

“I wasn’t stressing about it too much, and I definitely didn’t want to tell [Blue Jays manager Charlie Montoyo] about our little secret,” Choi added. “I just wanted to keep that to myself. ... Then today I felt pretty good, so why not?”

Though entering Sunday he had not taken an official at-bat from the right side in the big leagues, Choi does have some professional experience as a switch-hitter. The last time he hit right-handed was Nov. 25, 2015, during a Dominican winter ball game with Estrellas del Oriente.

Choi also hit right-handed in the Minors, but in 2015, he was told to focus on being a left-handed hitter. He slashed .296/.345/.389 in 54 at-bats from the right side of the plate.

“It’s truly incredible,” Rays center fielder Kevin Kiermaier said. “But if anyone can do it, it’s Ji-Man. He’s a man of many talents. I have to tip my hat to him on that because it’s not hitting your natural way, let alone picking up switch-hitting again four or five years later and crushing a homer the way he did. Incredible.”

So is Choi an official switch-hitter now? He won’t be tipping his hand.

“I still don’t know,” Choi said with a smile. “Maybe.”