Already laboring to reach his eighth straight NBA Finals with a supporting crew made mostly of cast-offs and throw-ins, James lost the only other All-Star on the roster on Saturday when Kevin Love was declared out for the series finale with a concussion.

Now, in what could be his final game in a Cleveland uniform — again — James will have to do it largely on his own.

In Boston, where the Celtics are perfect so far this postseason.

And in a series where the road team hasn’t really even come close.

“There’s something different about LeBron, period,” Cleveland forward Larry Nance Jr. said after James scored 46 with 11 rebounds and nine assists on Friday night to send the series to a decisive seventh game. “I think (coach Tyronn Lue) said it best: ‘We’re going into a Game 7 with the baddest dude on the planet on our team.’ I like our chances.”

James is having what could be the best postseason of his career, averaging 33.9 points and just under nine assists and rebounds, with seven 40-point games, two buzzer beaters, and a sweep of top-seeded Toronto. But he’s played in every game this season — Sunday will be his 100th — and it showed in the Game 5 loss to the Celtics.

He admitted to fatigue afterward, and then played all but two minutes in Game 6 despite a sore knee from a collision with Nance.

Still, the four-time MVP carried his team even after Love banged heads with Boston’s Jayson Tatum in the first half and left the game.

“I can’t say enough good things about him,” Celtics coach Brad Stevens said. “Every time we watch. Every time you’re standing out there. Every time you watch him on film. Best player in the game.”

James will probably have to do it again in Game 7 to reach the NBA Finals for the eighth straight year, something accomplished only by Bill Russell and some of his Celtics teammates in the 1960s.

Lue said he wasn’t concerned about James’ leg. Or about the team’s history in the TD Garden, where the Cavaliers lost the first three games by an average of 17 points.

“We throw it all out,” Lue said on Saturday. “It’s one game left to go to the NBA Finals.”

The Celtics have had their own injury problems, starting in the first quarter of the season opener — at Cleveland — when top free agent Gordon Hayward went out for the year with a broken leg. Five-time All-Star Kyrie Irving, acquired from the Cavaliers in an offseason roster overhaul, needed knee surgery and was lost in March.

But they caught a break when Tatum was cleared to play on Saturday. Stevens said the team doctors checked on him “and he’s great.”

“So nothing there as far as to be concerned about,” Stevens said.

Well, there’s one thing to be concerned about.

“We know LeBron is different than a lot of other guys, but we’ve got to get the job done,” Celtics guard Terry Rozier said. “That’s no excuse, so we’re looking forward to it.”

For James, it’s an opportunity to extend the season for his hometown team and put off another summer of questions about his future. Eight years ago, he came to Boston for the conference semifinals and had a triple-double — 27 points, 19 rebounds and 10 assists — but shot 8 for 21 with nine turnovers and the Celtics eliminated the Cavs from the playoffs.

As he left the court, James stripped off his Cleveland jersey; then came “The Decision” and the move to Miami.

James is again able to become a free agent this season, with the Lakers, 76ers and Rockets among the most-mentioned destinations. Having led Cleveland to the city’s first major sports title in half a century in 2016, there is less pulling at him to stay home this time.

But another title would ease the pain even more. And with the injury bug hitting the Western Conference finalists — Chris Paul was the latest ruled out for a game — the East champion might not be as big an underdog as expected.

James will be ready.

“You’ve got to be poised. You’ve got to be able to handle a punch or two,” he said. “We know it’s challenging. They’re 10-0 on their home floor, and they’ve been very successful against us, obviously, at home. But if you love challenges, then this is a great opportunity.”