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With Kyrie Irving traded, Isaiah Thomas never regaining form and Kevin Love missing a quarter of the season to injury, LeBron James has almost single-handedly carried the Cleveland Cavaliers all season.

Now, even his limits will be tested.

As the Cavs enter Game 7 against the Boston Celtics with a trip to the NBA Finals on the line, they'll do so without Love, their second-leading scorer and only other All-Star.

Love has been ruled out for Game 7 after accidentally bumping heads with Celtics forward Jayson Tatum in the first quarter of Game 6. As the Cavaliers announced, Love must clear the concussion protocol to play again this season:

Kevin Love was evaluated today prior to the team’s flight to Boston this afternoon. He is experiencing concussion-like symptoms and has been placed in the league’s concussion protocol. He is now listed as Out for tomorrow night’s game in Boston. His status will be updated as appropriate.

It's been no secret that winning in Boston has been nearly impossible for visiting teams. The Celtics haven't lost a home game since April 8 against the Atlanta Hawks, a night they played their starters limited minutes while resting up for the postseason. Boston is a perfect 10-0 in its building since the playoffs started and 3-0 against the Cavaliers.

Outside of James, Love was the only Cav enjoying any sort of success in Beantown. In those three road games, Love was giving Cleveland 17.7 points, 10.0 rebounds and 2.3 assists. The next highest-scoring Cavalier? Backup guard Jordan Clarkson with 9.0 points, a number taken with only a two-game sample, given that he was benched in Boston for Game 2 after struggling nearly all postseason.

James' scoring away from Quicken Loans Arena in this series is impressive (27.7 points, 47.8 percent shooting), but is nowhere near the remarkable 39.0 points on 57.5 percent shooting and 64.3 percent from three he's putting up at home.

It took 46 points from James in just over 46 minutes for the Cavaliers to even force a Game 7 without Love, and that was in Cleveland. George Hill chipped in a postseason-high 20 points, while Jeff Green (14 points) and Larry Nance Jr. (10) were the other Cavs in double figures.

This has been the overwhelming theme in these Eastern Conference Finals; role players playing well at home and vanishing on the road. If history holds true, James will be on his own in Game 7 at Boston.

Cavs Role Players vs. Celtics, Home/Away Splits Player Home PPG Away PPG Diff George Hill 15.3 5.0 -10.3 Kyle Korver 11.3 7.7 -3.6 JR Smith 8.3 2.0 -6.3 Tristan Thompson 8.3 5.7 -2.6 Larry Nance Jr. 8.3 0.7 -7.6 Total: 51.5 21.1 -30.4 NBA.com

A Game 7 victory would add yet another chapter to his incredible 2017-18 postseason.

James is first among all players with 33.9 points per game, while also leading in total minutes (695), field-goal makes (214), field-goal attempts (393), assists (149), player efficiency rating (33.5), box plus-minus (14.8) and value over replacement player (2.9). This is only the second time in his 13 postseasons that James has led the NBA in postseason scoring, player efficiency and total minutes. The other time? Six years ago with the Miami Heat, winning his first NBA championship.

We've seen a similar act play out before with James, during his first Finals run after returning to the Cavaliers in 2014-15.

That postseason Love also went down, this time with a separated shoulder against these same Celtics in the first round. Kyrie Irving later fractured his kneecap in overtime of Game 1 against the Golden State Warriors, leaving James in a starting five with Iman Shumpert, Matthew Dellavedova, Tristan Thompson and Timofey Mozgov.

Put any player in the league today around those four, and how many games in a playoff series could he realistically win? One? Any? James piled them all on his back and beat the Warriors twice, including an overtime victory at Oracle Arena.

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With no Love, this is a remarkably similar roster to the one James had to scratch and claw with three years ago. These Celtics aren't nearly as talented as those Warriors were, but they've played like it at home.

Cleveland will now be forced to alter its starting lineup. Hill and Smith will almost assuredly start once again in the backcourt, even though they've combined to average just 7.0 points per game in Boston.

Tristan Thompson has earned the starting center job, which leaves head coach Tyronn Lue to decide what he wants to do with James. If Cleveland goes small, it can use James as the starting power forward in place of Love and reinsert Korver as the team's starting small forward like it did in Game 1.

Lue can also try to stay big to combat Boston's frontcourt duo of Al Horford and Aron Baynes, but that means making Jeff Green the starting power forward.

On a team desperate for offense on the road and without Love, Lue needs to go small and put shooters around James. The three-man frontcourt combination of James, Thompson and Korver has a net rating of plus-10.6 in 69 minutes together this postseason. Swap Green in for Korver, and this rating drops to minus-11.5 in 98 total minutes.

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If Lue gets desperate enough for scoring, he may be forced to dust off Rodney Hood. That's where Cleveland is right now without Love.

This may be James' greatest personal challenge since those 2015 Finals, even more so than climbing back from a 3-1 deficit to lead the Cavaliers to their first title in franchise history in 2016. Love also suffered a concussion in that series, but James at least had Irving, who averaged 27.1 points per game and put up 41 in Game 5. Now, there's not a single healthy Cav outside of James who's even averaging over 9.0 points where Cleveland's about to play.

A loss would end the Cavaliers' season and James' streak of seven straight NBA Finals, and six weeks would await before the start of free agency.

A win would advance the Cavs to their fourth straight championship round, this time with a chance to play someone other than the Warriors. Should a Houston Rockets team without an injured Chris Paul advance and Love get cleared to return, anything can happen with James playing at this level. It also delays the amount of time James can sit at home and ponder his future.

James has already dazzled us with one of the most impressive postseason performances we've seen from anyone—much less in a 15th season.

In what could be the most important non-Finals game of his career, James will once again be asked to hoist a franchise on his back, gathering what energy he has left and getting the Cavs a victory—possibly for the final time.

Greg Swartz covers the Cleveland Cavaliers for Bleacher Report. Stats provided by NBA.com and Basketball Reference unless otherwise noted.