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Boston Celtics forward Marcus Morris shouldered some of the responsibility for his team's 116-86 loss to the Cleveland Cavaliers in Saturday's Game 3 of the Eastern Conference Finals at Quicken Loans Arena.

"I did a s--t job defensively against LeBron," Morris said Sunday after the loss, per Michele Steele of ESPN.

James finished with an impressive stat line of 27 points, 12 assists, five rebounds, two steals and two blocks as Cleveland won its first game of the series, but Boston still holds a 2-1 lead with Games 5 and possibly 7 set to be in TD Garden.

To be fair, James was far from the only Cavalier to play well in Saturday's contest. Six others scored in double figures, including all five starters, in an uncharacteristically poor performance from Boston's typically stellar defense.

The Celtics finished first in the league in defensive rating during the regular season, per NBA.com, and held the Cavaliers to less than 100 points in each of the first two games. But that defense was nowhere to be found in Game 3, as the three-time defending Eastern Conference champions drilled 17 three-pointers.

Morris wasn't happy with his own performance on James, but defending one of the best players in NBA history—for multiple games in a row—is no easy task.

He also didn't back down from the challenge going into the series, saying, "Personally, I think [I am] probably the best guy defending him in the league, outside of Kawhi," per Jay King of The Athletic.

As ESPN Stats & Info shared, Morris backed up his words in Games 1 and 2:

The Celtics are still in control of the series with a 2-1 lead but will need a better defensive showing if they are going to advance to the NBA Finals. Morris' ability to at least keep James in check is a significant part of that.