Mo Williams, LeBron James and the Cavaliers didn't hold back in celebrating Sunday's victory over the Celtics -- and some Boston players weren't too happy about it afterward.

AP photo / Mark Duncan

BOSTON – We are less than one week away from the start of the NBA playoffs, and the Boston Celtics are coming off their most embarrassing and lopsided loss of the season, a 107-76 setback to rival Cleveland.

Should Celtics fans be worried?

If you ask the Celtics, they will tell you no.

“I don’t think this loss really did anything to shake our confidence, because we feel like we can come in here and win a ballgame when we have to, so, hopefully, if we meet in the conference final, we’re confident we can get the job done in this building,” Celtics captain Paul Pierce told The Boston Globe after the game.

The Celtics say they shouldn’t be worried, because they had nothing to play for and were playing short-handed.

The playoffs could be a whole different story. The Celtics hope to be at full strength when the playoffs start, and their mission will be to successfully defend their NBA title.

On the other hand, there is no telling just how healthy 12-time All-Star Kevin Garnett (sore knee) will be once the playoffs start, and the same goes for forwards Leon Powe (knee) and Brian Scalabrine (post-concussion syndrome).

Another reason for concern is that Cleveland will have home-court advantage in the postseason this time around if the two teams meet in the Eastern Conference Finals, and the Cavs are undefeated at home against Eastern Conference opponents.

Only time will tell if the Celtics and the Cavs meet again for another playoff series this season.

On Sunday, the Celtics already knew they had the second seed in the East, while the Cavs were still fighting with the Lakers for the top overall spot in the playoffs. Cleveland had much more at stake in the game.

By getting the win, the Cavs became just the sixth team in NBA history to win at least 39 home games.

Each of the previous five teams made it to the Finals, and a win against Philadelphia on Wednesday would tie Cleveland with the 1985-86 Celtics for all-time best home record (40-1).

When teams have something to play for, they play harder, and that probably had something to do with Cleveland outscoring Boston, 31-9, in the first quarter on Sunday.

As for Garnett, the heart and soul of Boston’s defense, the Celtics are a much better team with him on the floor.

When Garnett is in the game, the Celtics play defense at a higher level, and offensively he provides Boston with another dangerous scoring threat.

Then again, Boston’s health could be cause for concern.

When the Celtics’ injured players return to the lineup, they will be playing with limited practice time and in-game situations over the last two months.

Boston’s chance of repeating as NBA champs is slim at best if Garnett is not healthy.

Home-court advantage has been a key in recent meetings between Cleveland and Boston. The Celtics have lost 11 straight games at the Quicken Loans Arena, where they would have to win at least once in order to beat the Cavaliers in these playoffs. The Cavaliers, meanwhile, are 0-8 in Boston since the arrival of The Big Three.

“We only get seven games, but the seventh game isn’t in our building,” Boston guard Ray Allen said of a possible matchup with Cleveland. “That’s the difference. We can’t have a struggle. We have to win one game here.

“You take it one game at a time in the playoffs. You’ve got to beat them, whoever you play. As the momentum builds, the playoffs build, and the teams start to dwindle. That is what it’s going to come down to, winning in this building.”

The Celtics haven’t won in Cleveland since a 114-107 overtime victory Dec. 18, 2004. They have lost by an average of 12.7 points during the 11-game stretch of losses.

“It’s not something the players think about, like when we come in this building that we can’t win, because we feel like we can win in this building,” Pierce said.

Sunday’s embarrassing loss, coupled with Cleveland’s boisterous celebrations on the sideline, will provide the Celtics with extra motivation if the two teams meet again in the playoffs.

“I’m always going to remember that,” Allen said. “If I beat a team, as happy as I may be in victory, I’m always going to stay humble and always remember that there’s another day. We play each other too much. Those are great motivational thoughts for me.”

Cleveland superstar LeBron James said the Cavs weren’t mocking the Celtics by their actions.

“We’re out there having fun,” he said. “When we are on the court, we don’t disrespect anybody and we don’t fear anybody. It is no disrespect to any team, but we have our own thing. We’re all professionals, and if you take it as disrespect then you have to do something about it.”

The Celtics hope to do something about it in the Eastern Conference Finals. Even with the loss, Boston has still won 11 of its last 13 games.

“I’m confident in this ball club anywhere, any day, anytime,” Pierce said.

roblee@projo.com