The Boston Celtics' 2026-27 campaign began with what will likely be one of their worst losses all season.

During Tuesday's season opener in Detroit, the Celtics held a comfortable 22-point lead early in the third quarter after offseason addition Paul George drilled three 3-pointers in under a minute. They had all of the momentum on their side, then watched it slowly slip away as the third quarter went on.

By the end of the third, the Pistons cut the deficit down to six. They pulled ahead in the fourth quarter with a resounding 23-0 run, fueled by timely buckets from bench contributors Duncan Robinson and Javonte Green.

Boston was outscored 76-55 in the second half, resulting in a devastating 121-113 defeat. The loss spoiled a stellar Celtics debut for George, who finished with 38 points on 12-of-21 shooting (7-12 3-PT).

Former Celtic Eddie House shared his instant reaction to the collapse on Postgame Live.

"They were making shots, we weren't making shots in that fourth quarter. They went on a big run and we could not stop it," House said. "We had our main guys on the bench that whole time, especially a guy like Paul George who in 31 minutes had 38 points. You would think that you would try to put him out there, but at the same time, it's game number one, you can't overreact to it.

"But at the same time, you do want to react to the fact that you were up 22 and squandered that lead. You were in control of that basketball game, and the next thing you know, they were in control of the basketball game."

NBC Sports Boston's Celtics insider Chris Forsberg echoed House's sentiments, noting that blowing a lead in this manner isn't exactly new for the Joe Mazzulla-led C's.

"That second half was pretty embarrassing, and really over the three minutes that they kicked away the lead and watched them go on an 18-0 run that snowballs to 23, you've just got to be able to collect yourself quicker in that instance, whether that's Joe doing what he can to get them reeled in or the players themselves finding a way to settle down," Forsberg said.

"This is something the Celtics have been prone to in previous seasons. Discouraging to see it crop up this early. It takes away from a lot of the good they did late in that first half, overcoming an ugly start."

Mazzulla's group will look to improve in several areas when they host the New York Knicks for their home opener on Friday. They were outrebounded 49-39, with their top two centers Mitchell Robinson and Neemias Queta combining for only seven boards. They also turned the ball over 14 times.

Superstar Jayson Tatum scored only 13 points on 6-of-23 shooting (0-7 3-PT). He tallied 11 assists, but he simply didn't do enough offensively to keep the C's afloat while the Pistons got red-hot in the fourth.

Fortunately for the Celtics, they have plenty of time to turn things around. Game 2 of the season vs. New York is set for 7 p.m. ET Friday at TD Garden.

Watch the full Celtics Postgame Live segment below: