After defeating the Milwaukee Bucks on Friday, the Celtics are back in action and welcome back old friend Marcus Smart and the Memphis Grizzlies. Last year, Smart was injured and couldn’t play his first game at TD Garden, so this will be his first game against his former team. Smart was the heart and soul of the Celtics for nine seasons, and while it still looks strange to see him in a Grizzlies uniform, it’s nice to see him playing on the floor again.

Al Horford is out for the second half of a back-to-back game tonight and Kristaps Porzingis, the key player in the Marcus Smart trade, returns for the Celtics. The Grizzlies lost Zach Edey, Luke Kennard and Vince Williams Jr.

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Marcus Smart entered the game for Memphis at 8:50 and received a standing ovation from the TD Garden crowd.

It was a back-and-forth affair to start the first quarter, but the Celtics’ offense got off to a sloppy start. Boston started the game 2-for-11 from three goals, including Jrue Holiday’s 1-for-6. The Grizzlies’ defensive strategy of “make Jrue Holiday beat us” worked early as they went on a 10-0 run to build a 10-point lead.

The Holiday strategy didn’t work for long, however, as Holiday drilled back-to-back wide-open threes in the corner. Holiday finished the first quarter with 11 points on 4-10 shooting and 3-8 from distance.

Smart got a rude awakening in his return, shooting 0-for-5 in the quarter, including a block from Neemias Queta that led to a hustle from Payton Pritchard to keep the ball from going out of bounds.

The Grizzlies’ role players came up big as players like Jay Huff, Santi Aldama and Jaylen Wells helped Memphis maintain a 31-27 lead over the Celtics at the end of the first quarter. Holiday led the Celtics with 11 points in the quarter and Ja Morant also led the Grizzlies with 11 points.

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After Neemias Queta was the Celtics’ first center off the bench in the first quarter, Luke Kornet started in the second quarter.

Jaren Jackson Jr. and Brandon Clarke took the Grizzlies’ lead early in the second quarter and began picking on Kornet when Ja Morant lobbed to Clarke, who dunked right over him. The Celtics would be without Sam Hauser for the remainder of the game as his return in the second quarter was doubtful due to right adductor tightness.

Points in the zone were a real problem for Boston, as the Grizzlies outscored the Celtics 32-14 in the first half, highlighted by Clarke’s eight-pointers in the second quarter on 4-4 shooting in the paint area became. Memphis continued to leave Holiday open and it started to work as his three balls didn’t fall and he made a career-high 17 shot attempts in the first half, only five of which went down.

A somewhat frightening sight for Boston, with 1:35 left, Kristaps Porzingis was heading back to the locker room when a misstep resulted in an apparent ankle sprain that left him limping.

The Celtics’ sloppy play continued as they too began to look like a team that had played five games in seven days. To end the half, they turned the ball over one after the other, leading to a layup by Morant and an impressive block by Derrick White on Desmond Bane as the Celtics took a 66-54 lead into halftime.

Jrue Holiday finished the half as the Celtics’ leading scorer with 16 points on 5-for-17 shooting (4-for-12 from three). Holiday was the only Celtic in double figures at halftime as Boston shot 18-50 (36%) from the field and 9-31 (29%) from three. Jayson Tatum and Jaylen Brown scored just 6 points in the half, with Tatum having a difficult shooting distribution of 3-for-11 from the field and 0-for-7 from three.

At Memphis, Ja Morant led the Grizzlies with 15 points, 8 rebounds and 7 assists while dismantling the Celtics’ defense. Jaren Jackson Jr. (13 points) and Brandon Clarke (12 points) were also key factors as Boston had no answer for them at the rim.

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Memphis continued to force Holiday to beat them and Jrue continued to shoot but couldn’t take advantage of the open looks. A good sign for the Celtics came when Porzingis started the third quarter of the game and hit back-to-back threes to cut the Grizzlies’ lead to six.

The Grizzlies were able to counter the Celtics’ comeback attempt when Ja Morant took over. He found Brandon Clarke for an alley-oop, hit a mid-range shot over White and finished with a highlight reel, double clutch and behind-the-head dunk that stunned the TD Garden crowd.

Once Morant went to the bench, the Celtics began to find their offense. Porzingis and Tatum each scored a layup off Jay Huff at the rim, Queta got free throws on a rebound attack, Porzingis got a free throw after a foul off an inbounds and Payton Pritchard drained a three-pointer.

A 12-3 run cut the Grizzlies’ lead to 2, but Ja Morant checked in and hit consecutive three-pointers to push the lead back to 5 as Memphis took a 94-89 lead early in the fourth quarter. Kristaps Porzingis and Jayson Tatum were the main catalysts for the Celtics’ third quarter rally, as they combined for 30 of the Celtics’ 35 points in the quarter.

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The Celtics offense continued to roll early in the fourth quarter as a mid-range shot from Payton Pritchard, a three-pointer from Jaylen Brown and another three-pointer from Pritchard gave the Celtics their first lead of the night with 10:32 to play, much to the delight of Ean Horford on the bench.

At the 9:20 mark of the quarter, Jrue Holiday scored a layup against Ja Morant, scoring the 16,000th point of his career.

The Celtics fielded a lineup twice as big with Kornet and Queta that didn’t produce great results. The Grizzlies would retake the lead as Jaren Jackson Jr. scored 11 straight points for Memphis, but Jaylen Brown would match him almost every time to keep Boston in the game.

Both teams continued to battle back and forth as the Celtics had several chances to retake the lead but were unable to make a three-pointer. The Grizzlies began to pull away slightly when Desmond Bane’s three-pointer and layup gave Memphis a nine-point lead with under two minutes left.

Jaylen Brown hit a turnaround three over Morant to cut the score to 6, and then chaos ensued when White went for a loose ball, Jackson pushed him to the ground, resulting in a no foul being called, much to the detriment Horror of the Garden audience. Morant and Pritchard exchanged a 1-2 count from the free throw line, and Brown intercepted a pass that led to a layup, giving the Grizzlies a four-point lead with 21.7 seconds left.

After a Grizzlies timeout, an inbound pass to Jackson Jr. resulted in a jump ball. Porzingis won the tip-off and the ball went to Bane out of bounds, the Celtics ball with 17.1 seconds left. However, Memphis challenged and won the out-of-bounds call, the Grizzlies ball.

Desmond Bane hit two free throws, Pritchard missed a three-pointer, White missed a three-pointer and the clock went to zero as the Grizzlies beat the Celtics 127-121. This is the first time in his career that Jayson Tatum will lose to Memphis as Marcus Smart wins his first game at TD Garden as an opponent.

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Ja Morant led the Grizzlies in this game, posting 32 points, 9 rebounds, 9 assists, 2 steals on 11-20 shooting and 4-6 from three. Jaren Jackson Jr. also had a big game with 27 points and 9 rebounds.

Jrue Holiday would be the Celtics’ leading scorer with 23 points, 8-26 from the field and 4-17 from three. Jaylen Brown and Payton Pritchard would also both have 22 despite the loss.

The Celtics have four days off between their next game on Thursday, Dec. 12 against the Detroit Pistons, as that game was added to the schedule after Boston failed to qualify for the NBA Cup playoffs.