Trailing 5-4 in the ninth, Murakami, who had struggled through much of the tournament, drove a pitch to the wall in the centre at Miami's LoanDepot Park to send the two-time champions into tomorrow's final against the defending champions United States, in a rematch of the 2020 Olympic final in Tokyo. 

Murakami, who had been 0-for-4 after last year becoming Japan’s youngest triple crown hitter, blasted a high fastball from St. Louis Cardinals reliever Giovanny Gallegos into the deepest part of the ballpark before a crowd of 35,933, the biggest of the tournament in Florida so far.

"Having struck out three times, the thought of bunting in that situation crossed my mind, but the manager wanted me to swing, and I had a good feeling from my previous at-bat when I flied out," Murakami said.

Japan manager Hideki Kuriyama was delighted the 23-year-old Tokyo Yakult Swallows star had come good when it mattered. 

"I believe he [Murakami] had been feeling bad, but I believed in him," Kuriyama said.

Major League Baseball Los Angeles Angels star Shohei Ohtani, nicknamed "Shotime" and considered the sport’s biggest star after last year becoming the first player in the modern era to qualify for both the hitting and pitching leaderboards in one season, had sparked the rally with a lead-off double.

As he stormed to second base, he took off his helmet and roared and wildly gestured with his arms to urge his team-mates on.

Masataka Yoshida followed with a walk, and the 2022 Triple Crown winner in Japan's Central League ended the wild game with one last thrill as Ohtani and pinch-runner Ukyo Shuto scored easily.

"We knew it wasn't going to be an easy win," Ohtani, who has been called the greatest two-way player since Babe Ruth, said.

"But no one thought it would be in a game like this."

Mexico took a fourth-inning lead on Luis Urias' three-run home run off Roki Sasaki, but Japan tied it on Yoshida's three-run home run in the seventh.

Yoshida, a new Boston Red Sox outfielder, took his World Baseball Classic-leading runs batted in (RBI), a statistic in baseball that credits a batter for making a play that allows a run to be scored, total to a record 13.

Randy Arozarena, who robbed Japan of a fifth-inning lead-off homer, doubled and scored to spark a two-run eighth-inning rally that gave the Mexicans a commanding lead until the late rally.

Mexico manager Benji Gil, whose team came from behind to dispatch Puerto Rico in the quarter-finals and reach the WBC semi-finals for the first time, summed up the game.

"We have to take our hats off to Japan," Gil said.

"Neither team deserved to lose, but someone had to win.

"Both teams had a great performance, great pitching, and at no point in time gave up or surrendered.

"Japan moves on, but the world of baseball won today."

The win sends Japan back to the final for the first time since 2009, when they won their second title having lifted the trophy in the first edition of the World Baseball Classic in 2006, after two consecutive semi-final exits.

Japan had beaten the US 2-0 in the final of the re-arranged Olympic Games at the Yokohama Stadium in 2021. 

"On the ultimate stage, we're facing the toughest opponents," Ohtani said.

"I'm really looking forward to tomorrow.

"Naturally, it's going to be tense, but I want everyone to give their all with a strong desire to win whatever it takes."