BOSTON — When the Celtics sent Rajon Rondo to Dallas last month, they received three players in return.

One already has been shipped out of town. Another seems resigned to ride the bench in street clothes until he’s moved, as well.

As for the third? Well, he’s quickly grown into one of Boston’s most important players.

That man would be Jae Crowder, the least-heralded of the Rondo Three but the one who has made by far the greatest impact.

Crowder quickly has risen from late-game energy guy to key reserve to starter — a spot cemented when he poured in a career-high 22 points to go along with three rebounds, three assists, four steals and two blocks Monday night at TD Garden in a 108-100 win over the New Orleans Pelicans.

Crowder logged a team-high 36 minutes in the game, the third straight he started since taking over for the recently traded Jeff Green as Boston’s starting small forward, but never lost the trademark intensity that immediately endeared him to coach Brad Stevens.

“Because he’s tough,” Stevens said before the game when asked why he likes Crowder in his starting five. “I just like his toughness. I like his grit. I like his stuff. He’s not perfect technically. He hasn’t played in our system defensively, and there’s going to be some mistakes here and there, but nobody questions his toughness.”

It’s a toughness Crowder developed during his college days at Marquette — the team that, coincidentally, ended Stevens’ college coaching career in the 2013 NCAA tournament.

“When I was at Marquette, (coach) Buzz Williams would install a hard-playing type of mentality in me,” Crowder said. “I always played with a little passion, but he installed the hard work and the hard play.”

Jared Sullinger took over the offensive reins in the fourth quarter (13 of the big man’s 27 points came in the final frame), but Crowder made his one basket count, burying a bank-shot 3-pointer from straightaway to put the Celtics up four with 4:56 to play.

Crowder raised up his arms as the bucket fell, as if to ask the Garden faithful: “Are you not entertained?”

They certainly were.

“(The fans were) unbelievable,” Crowder said. “They pushed me. Like I told the guys, if you can’t play for anyone, you can for this crowd.”

Thumbnail photo via Mark L. Baer/USA TODAY Sports Images