The Boston Celtics have been one of the biggest disappointments thus far, as the pre-season Eastern Conference favorites sit at a mere 12-10 through the first quarter of the 2018-19 season.

Though All-Star point guard Kyrie Irving is having another phenomenal season, veteran Gordon Hayward has performed well below his usual standards. Youngsters Terry Rozier, Jaylen Brown and Jayston Tatum have failed to regain the star-like forms they displayed during the postseason.

Celtics legend Paul Pierce - who led the team to an NBA Championship in 2008 - has seen it all through his career. He played on some very bad teams, and some great Boston teams that featured other superstars.

Pierce offered some advice to the struggling Celtics, warning them to learn to play as a team if they want to win.

"Sacrifice is going to be the word I constantly say about them," Pierce said, via A. Sherrod Blakely of NBC Sports Boston. "They have guys capable of being 20-point scorers but on this team that’s not going to happen...If you want to win, you have to sacrifice. Some nights it may be your night. Some nights it may not be your night."

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Pierce talked about how he did less scoring and contributed more rebounds and defensive work when the C's acquired Kevin Garnett and Ray Allen in the 2007 offseason. While Pierce's scoring went down, it made the Celtics a force that won the aforementioned NBA Championship in 2008.

The Celtics have plenty of flashy players, but the lack of team chemistry has been evident. Tatum and Brown have been criticized for trying to take too many hero shots, and Rozier has been expressed dissatisfaction with his reduced playing time.

Nonetheless, Pierce warns the Celtics players to put the team first.

"They want to establish themselves. They want to make a name for themselves," Pierce said. "You make a name for yourself by winning."

What This Means

The Celtics would be wise to listen to Pierce, who learned the value of sacrificing individual stats for team success. If this Boston group wants to reach its potential and vie for an NBA Championship, they'll have to learn how to play a team game first.

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