Shohei Ohtani was described as a "unicorn to the sport" by United States manager Mark DeRosa after he led Japan to victory in the World Baseball Classic final.

Ohtani struck out Los Angeles Angels team-mate Mike Trout to seal a 3-2 victory in a thrilling conclusion in Miami on Tuesday.

Named the tournament's MVP, Ohtani ticked off a list of achievements during the game that had only ever previously been matched in an MLB or WBC game by the legendary Babe Ruth in October 1921.

The 28-year-old started in the batting lineup, drew a walk, got a hit, came on to pitch in relief, struck out a batter and was the finishing pitcher.

"What he's doing in the game is what probably 90 per cent of the guys in that clubhouse did in Little League or in youth tournaments, and he's able to pull it off on the biggest stages," DeRosa said. 

"He is a unicorn to the sport. I think other guys will try it, but I don't think they're going to do it to his level.

"What blows me away on this stage is the fact that no moment is too big for him. He did not seem rattled by walking Jeff McNeil on a close pitch, not rattled that three MVPs were coming up to bat."

Ohtani himself was happy to accomplish one of his career goals by winning the tournament, and believed the victory over the USA was also proof that Japan can get the better of anyone.

"In my baseball life, [winning the World Baseball Classic was] one of the things that I wanted to achieve," Ohtani said. "Today I was able to achieve one of the goals.

"Of course, I happened to get the MVP, but this really proves that Japanese baseball can beat any team in the world."