The Toronto Raptors have won their first NBA title after defeating defending champions the Golden State Warriors in a nail-biting end to game six.

The Raptors overcame the Warriors 114-110 to take the best-of-seven series 4-2, despite Golden State coming close to forcing a seventh game.

With the teams a point apart in the final second, Kawhi Leonard hooped three free throws to lift the Raptors clear.

Pascal Siakam and Kyle Lowry scored 26 each for Toronto, while Leonard and Fred VanVleet racked up 22 each.

Klay Thompson scored 30 for the Warriors, who were denied a seventh game which could have given them a seventh title.

"This is what I play basketball for," said MVP Kawhi Leonard: "This is what I work out for."

Playing in his first season with Toronto, Leonard averaged 28.5 points during the best-of-seven Finals, leading Canada's only NBA team to a 4-2 series upset of two-time defending champions Golden State.

Playing against a Warriors team with Stephen Curry and Klay Thompson, two of the NBA's most feared shooters, Leonard dazzled in the spotlight and left his rivals in the shade.

The focal point of the Raptors offense throughout the Finals, he took the playmaking responsibilities on his shoulders and shrugged off Golden State's efforts to slow him down.

The Raptors became a legitimate contender when they dealt DeMar DeRozan to San Antonio as part of a blockbuster trade to acquire Leonard last July.

When Leonard arrived, he was coming off a season in which he missed all but nine games with a quadriceps issue and it was no great secret that his preferred destination was his birthplace of Los Angeles.

"I just came in with the right mindset, let's go out and win ball games," said Leonard.

"I texted Kyle (Lowry) probably a day later -- or the day that I got traded and told him I said let's go out and do something special. I know your best friend left, I know you're mad, but let's make this thing work out. And we are here today."

With no assurances that Leonard would re-sign with the team beyond 2019, it was a high-risk trade for Toronto.

The rewards, however, have been huge.

Leonard led the team in scoring all season and carried them to their first final in the franchise's 24-year history.

After being presented with the MVP award, Leonard was asked how winning a championship would shape his pending free agency decision.

"I'm about to enjoy this with my team mates and coaches and I'll think about that later," he replied.