Observations after Nets put on quite an exhibition in blowout of Celtics

Former Celtic Kyrie Irving drives past Robert Williams during the Nets' blowout win at TD Garden.John Tlumacki/Globe Staff

TD Garden has sat mostly dark and vacant for the last nine months, big crowds and big games silenced by the COVID-19 pandemic. On Friday night the lights came on and a basketball game was played there for the first time since March.

Not much about the Celtics’ preseason game against the Nets felt normal. There were no fans. Coaches wore masks. But it was a game and it was a start.

“I think we all look for these little tidbits of normalcy,” coach Brad Stevens said.

While the Celtics probably felt good to be playing on their home floor again, there will be no cheery highlight reel about the return. The new-look Nets, led by Kevin Durant and Kyrie Irving, took the lead less than three minutes into the game and never lost it, as they stormed to a 113-89 victory.

For the Celtics, the most encouraging aspect of this game was that it did not count. These teams will meet again on Christmas, and if that result is similar, there will be more cause for concern.

Jayson Tatum led the Celtics with 19 points on 5-of-17 shooting and Jaylen Brown added 16 points. The Celtics made just 34.8 percent of their shots overall and 17.8 percent of their 3-pointers. Durant had 25 points and Irving added 17 for the Nets.

“We’re not even close to that group that was in the bubble [in Orlando],” Stevens said. “We’ve got a lot of work to do to get to that point. We have to play a lot better than we have. Ultimately, we have to make sure we’re building the right habits.”

Observations from the game:

▪ The Celtics scheduled just two preseason games, the league minimum, and it’s unclear whether that was good or bad. Maybe they could use more time to tune up, or maybe they just need real games to show their best.

But what is clear is that the two losses this week were not pretty. Boston has appeared sluggish and disconnected, and has been unable to establish any rhythm at either end of the floor. Kemba Walker’s absence is a significant part of that, but he’s sidelined indefinitely, so sitting back and waiting for him is not really an option.

Tatum and Brown struggled with their long-range shots this week, but water will find its level there. The lack of reliable playmakers with Walker out and Gordon Hayward now in Charlotte could be glaring, and the lack of scoring punch when Tatum goes to the bench could be too much to overcome at times. Stevens might have a difficult time keeping Tatum’s minutes down.

“Obviously, we haven’t played well in the majority of these two games,” Stevens said. “And certainly our first group has not played well . . . So we’re going to have to make sure we get a lot better and get ready for Wednesday. We’ve got a really good team, Milwaukee, coming in. At the same time, these games are exhibition games for a reason, so we’ll learn from them and move on.”

▪ Celtics fans probably don’t love seeing it against their team, but it’s really good to see Durant back on an NBA court again. Durant, who missed all of last season after tearing his Achilles tendon in the 2019 NBA Finals, appears healthy and ready to reclaim his spot among the game’s elite. The late start to this season could be a blessing in disguise for him.

Boston rookie Payton Pritchard received a lesson from Durant in the second quarter. He was low and backpedaling as Durant pushed upcourt on a break, and Durant calmly pulled up and drilled a 3-pointer over Pritchard with no resistance.

▪ The Nets spent several possessions attacking Pritchard, who might be generously listed at 6 feet 2 inches, with mid-range post-ups. They got several clean looks in these sets but did not connect.

▪ This was not how anyone thought Irving’s first game in Boston since his departure after the 2019 season would look, but everything about this year is weird anyway. Irving, who missed both Nets games in Boston last season because of injury, embraced and chatted with most of his former teammates before and after Friday’s game.

“I’m grateful to be able to have relationships with a lot of these guys who are still here, guys who aren’t here still,” Irving said. “And, at the end of the day, we went to war together. And I respect all those young men down there. We’re not even young. We’re just young kings growing in a business where we want to do what makes us happy. To see Jayson get better, to see Jaylen get better, to see these guys mature and be in the positions they’re in, I’m nothing but proud of them.”

It will be factual to one day say that Irving was not booed during his return to Boston, even if it was only because there were no fans there to boo him.

▪ Center Daniel Theis returned after missing Tuesday’s game because of back soreness. He started in place of Robert Williams. Tristan Thompson remains sidelined because of a sore hamstring. His status for next week’s opener against the Bucks is in doubt, so Williams could be in line for a substantial role. His preseason was a microcosm of his career to this point, bursts of athleticism and potential mixed in with bewildering moments.

▪ Rookie Aaron Nesmith had a tough first half. Former Celtic Jeff Green dunked on him, he gave Joe Harris too much space for a pair of 3-pointers, and then he was whistled for an offensive foul when he kicked his leg out trying to draw contact on a 3-pointer.

“We got some young guys we’ve got to bring up to speed, and also just build some chemistry, and it’s on all of us,” Brown said. “Definitely doing a better job of communicating on defense, but I feel like as the season goes along we’re going to grow and improve in the right direction.”

▪ Finding positives on this night requires some squinting, but Stevens pointed out that second-year point guard Tremont Waters had a promising stint. Waters played the entire fourth quarter and registered 7 points, 5 assists, and 3 steals.

“I did think that our last group did a good job, and specifically orchestrated by Tremont,” Stevens said. “I thought he was very good really in both games in getting us organized. We can take something from how he’s led us, I think.”