The Boston Celtics knew they needed to get their act together after a disappointing loss to the Utah Jazz on Friday. Mission accomplished.

The Celtics shook off any lingering post-All Star break rust Sunday, exploding for 35 points in the first quarter en route to a 121-101 win over the Denver Nuggets at Pepsi Center. The Nuggets made things interesting with a big third-quarter run that cut Boston’s lead to five, but the C’s quickly responded with a run of their own and led by double digits for most of the night.

The Celtics spread the wealth offensively, with six players finishing in double figures. Isaiah Thomas led the way with 22 points and 12 assists, while Avery Bradley added 20 and Evan Turner contributed 17 off the bench.

Nikola Jokic scored a team-high 23 points for the Nuggets, who committed 24 turnovers on the night.

Isaiah Thomas, Avery Bradley, Jae Crowder, Amir Johnson, Jared Sullinger

The Celtics came out with a lot more energy Sunday, getting it done on both ends of the floor to open up a big early lead.

Boston’s aggressive defense, led as usual by Jae Crowder, forced Denver into seven first-quarter turnovers.

Thomas led the offensive charge, scoring or assisting on 18 of the Celtics’ first 21 points. The C’s used excellent ball movement to rattle off a 20-4 run at one point and shot 50 percent from the floor in the period.

The Nuggets didn’t fold up their tents despite a rough first quarter.

Denver’s anemic offense finally got going in the second frame, as Jokic and D.J. Augustin combined for 19 of the home team’s 32 points in the quarter. The Nuggets went on a 10-0 run midway through the period to cut their deficit to 16.

But Boston stayed afloat thanks to some sharp shooting behind the arc, as Bradley, Marcus Smart and even Evan Turner hit 3-pointers in the quarter.

The Nuggets took their momentum into the third quarter, capitalizing on some sloppy Celtics turnovers to pull all the way within five after a 13-2 run.

That’s as close as they would get, though, as Thomas scored several key buckets to help stem the tide:

Crowder and Jared Sullinger also elevated their game, each adding nine points in the quarter. Crowder’s layup-and-the-foul with 12 seconds remaining in the third pushed the Celtics’ lead to 16.

Boston flashed its trademark hustle down the stretch to hold off the pesky Nuggets, continuing to capitalize on Denver turnovers while closing the game out on a 20-10 run.

The Celtics scored 24 fast-break points and tallied 29 points off the Nuggets’ 24 turnovers.

After a disappointing showing in their first game without the injured Kelly Olynyk, Boston’s big men stepped up Sunday.

Sullinger (16 points, 11 rebounds) and Amir Johnson (6 points, five rebounds) had bounce-back games after combining for just 11 points Friday. Tyler Zeller also came to play, tallying nine points in 15 minutes of action, while Jonas Jerebko added six points on 3 of 5 shooting.

Smart’s diving tapout was the best part of this incredible hustle play by the Celtics early in the fourth quarter.

The Celtics will close out their three-game road trip Monday with a showdown in Minnesota against reigning NBA Slam Dunk Contest champion Zach LaVine and the Timberwolves. The Wolves own the NBA’s fifth-worst record at 17-39. Tipoff is set for 8 p.m. ET.

Thumbnail photo via Isaiah J. Downing/USA TODAY Sports Images

Thumbnail photo via Boston Celtics forward Jae Crowder (99) drives to the basket against Denver Nuggets forward Danilo Gallinari (8) in the first quarter at the Pepsi Center.