Leonard forced his way out of San Antonio Spurs last year and penned a surprise 12-month deal with the Raptors.
The small forward is considering all of his options thereafter, with a move to Los Angeles widely expected.
That would leave the Lakers and Clippers to battle for his signature.
And former Boston Celtics star Pierce reckons the 27-year-old will want to move closer to home.
“I think the only way he stays there (with the Raptors) is if they win the Championship,” Pierce exclusively told Express Sport at the PokerStars Players No Limit Hold’em Championship (PSPC) in the Bahamas.
“I think he is a California guy, he will end up on the Western Conference somewhere.
“But nobody really knows what Kawhi will do.
“I thought he had a great situation down there in San Antonio and obviously it wasn’t that great – he wanted out.
“But that is the beauty about basketball and free agencies and great players.”
If Leonard does move to southern California, Pierce has tipped the defensive maestro to turn his new side into Championship contenders.
“You know that a player can become a free agent and one player can change the fate of a franchise unlike every other sport,” he added.
“You get a guy like Kawhi, one player can go to LA Lakers, or go to Boston Celtics, that player is going to have a chance to win a Championship.”
Pierce was speaking at the Atlantis Resort & Casino where he entered the PSPC.
Unfortunately, the NBA star was knocked out on the first day but he enjoyed making his debut at one of the biggest poker events in the world.
“It was fun,” he said.
“It was a very, very tough field out here. A lot of these guys play for a living.
“They play much more than me but it was good to get my feet wet.
“Hopefully if I get to more and more tournaments I can get better.
“I lasted almost to the end of day one. I got knocked out towards the end with ace-queen versus jacks but lesson learned.”