Freddie Freeman hit a grand slam in the first extra inning to give the Los Angeles Dodgers a 6-3 win over the New York Yankees in the opening game of the World Series.

Down to their final out and trailing 3-2, Freeman defied a sprained ankle to hit the first walk-off grand slam home run in World Series history.

Anthony Volpe had put the Yankees ahead in the 10th inning, with his hit scoring Bahamas-born British international Jazz Chisholm Jr.

But they intentionally walked Mookie Betts to load the bases with two out and Freeman made them pay as he put the first pitch he saw from Nestor Cortes into the stands.

A Kike Hernandez triple had put the Dodgers 1-0 ahead in the fifth innings before Giancarlo Stanton replied with a two-run home run in the sixth.

Betts tied the score in the eighth with a sacrifice fly which drove in Shohei Ohtani.

Game two is at Dodger Stadium on Saturday night before the best-of-seven series moves to New York.