Four years ago in Japan, Lomano Lava Lemeki rose to the occasion as the 2019 Rugby World Cup hosts defeated Samoa on their unbeaten run through the pool stages.

On Thursday at Stadium de Toulouse, the 2016 Olympian repeated his heroics and was once again named man-of-the-match as the Brave Blossoms kept alive their hopes of reaching their second straight World Cup quarterfinals.

A surprise call-up to the squad, given his last test match prior to the tournament was in 2021 against Australia, Lemeki has made the most of his opportunities, starting in the loss to England when he came on in just the seventh minute as a replacement for the injured Semisi Masirewa.

At a packed stadium in Toulouse against a tough, physical Samoan team, Lemeki was once again Japan's rock at the back and their inspiration with ball in hand.

Early on, Japan's kicking game had been slightly wayward, and it was a perfectly placed up-and-under and chase from Lemeki that demonstrated what needed to be done.

Japan's first two tries were also the result of good breaks from the naturalized Japanese full-back, who carried for a game-high 151 meters.

Off the field, Lemeki's contributions have been just as important, even if he has not always enjoyed the training sessions.

"These camps have been really tough," he said. "We've been doing wrestling and stuff, which is not fun, but it seems to be working. We put a lot of emphasis on this game, but it is just a first step. We need to take it on to Argentina next week."

Lemeki's positive presence around the team has proven a mood lifter.

Rikiya Matsuda came into the tournament low on confidence but a press conference with Lemeki before the first game had him laughing, and the newly relaxed fly-half has since landed 15 of his 16 shots at goal.

Early this week, when the naturally shy Amato Fakatava struggled a little in front of a large media contingent, it was Lemeki who took the pressure off the big lock by telling jokes and translating a few of the questions into Tongan.

Japan coach Jamie Joseph defended Lemeki's initial inclusion on the grounds that he could play a number of different positions and roles.

If Lemeki can repeat his game-changing performance from Thursday night against Argentina, there will be few, if any, questioning Joseph over his decision.

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