“Payton Pritchard and Derrick White,” Horford said, still smiling. “That’s all you need to know tonight.”

While Pritchard conducted a television interview nearby, Horford and other teammates slithered behind him and dumped cups of cold water on his head. In the locker room later, White was ambushed with a much larger water bath, with Jaylen Brown even tossing a sneaker at him for good measure.

The Celtics are one of the most historic franchises in professional sports, and the championship banners and retired numbers that hang above the parquet floor are reminders of how difficult it is to find space in a record book anymore.

But Pritchard and White submitted improbable, riveting, and unforgettable scoring performances.

Pritchard erupted for 43 points and White poured in 41, career highs for both, and they became the first Celtics teammates to reach the 40-point mark in the same game, and the first duo in NBA history to connect on at least nine 3-pointers apiece. And less than a week after Brown and Jayson Tatum combined for 83 points against the Cavaliers to set the franchise record for a duo, Pritchard and White broke that record, too.

“Me and P were talking about it, and it was kind of crazy like, we weren’t even hitting the rim, just swishes,” White said.

Pritchard was 14 for 20 from the field and 10 for 16 from the 3-point line, and he was serenaded with “MVP” chants when he put the finishing touches on the win at the foul line. White made 14 of 26 overall and 9 of 17 3-pointers.

After the game, White scanned the stat sheet and said that Pritchard should have fired up a few more shots.

Both players received expanded opportunities with Tatum (rest), Kristaps Porzingis (illness) and Jrue Holiday (finger) all sidelined. But their explosive play gave the NBA a reminder of this team’s unusual depth, and ability to puncture a defense from so many angles.

“The way those two played showed a lot about who they are,” Celtics coach Joe Mazzulla said. “They do a lot of the dirty stuff when we’re fully healthy. They do a lot of things for the team, and to have a night like this where those two can show what they are capable of was big for us. So we’re lucky to have them, and it was a lot of fun to watch them do that.”

The record-breaking performances of Pritchard and White were unique, in part, because they were so efficient and simultaneous. They were not hunting shots. In fact, Pritchard attempted just three in the fourth quarter.

But the Celtics needed their scoring avalanche in order to hold off a pesky and improved Portland team.

“Sometimes when you get up in those numbers, you want to press and feed the hot hand and things like that,” Horford said. “That’s OK to an extent, but I just felt like they had a good balance of when to shoot, when to pass, when to move it. That’s pretty unique.”

Boston started the game by missing four 3-pointers in a row, but the slump was brief. Pritchard hit two in a row in quick succession, and with 2:30 left he drained a contested fadeaway from the right corner. White then connected on back-to-back deep 3-pointers before Pritchard’s catch-and-shoot dart from the left arc with 8.2 seconds left sent Boston to the second quarter with a 31-26 lead.

During the second quarter, White hit three 3-pointers over an 80-second stretch to help flip a seven-point deficit into a 66-55 halftime lead. White had six 3-pointers in the half and scored 24 points.

“It was amazing to watch,” Pritchard said, “because some of the shots he was hitting were incredible, too, and he wasn’t hitting the rim. Just straight water. So, definitely fun to be out there with him and do it on a special night like this.”

The break did nothing to cool down Pritchard or White. Pritchard started the second half in place of Luke Kornet to force Blazers big man Donovan Clingan to defend the arc.

A White 3-pointer stretched Boston’s lead to 81-63, and Pritchard took over soon after. He hit two more 3-pointers over a 42-second span, and then his 3-pointer from the left arc with 1:54 left gave the Celtics a 99-77 lead.

Pritchard had 19 points in the quarter, and by the end the crowd was buzzing with anticipation every time he touched the ball. There were even boos when the Blazers intentionally fouled him in the final seconds when they had one to give.

The Blazers chipped away at the deficit and pulled within single digits in the fourth quarter, but their mild run mostly just ensured that White and Pritchard would stay on the floor down the stretch. Both players received ovations when their respective career highs were shown on the video board during timeouts, and the celebratory sprays came later.

“It’s great to have that night along with [Pritchard],” White said, “and just kind of both of us just trying to play the right way and do what it takes to win.”

Adam Himmelsbach can be reached at [email protected]. Follow him @adamhimmelsbach.