Jayson Tatum #0 of the Boston Celtics looks on during the game against the New York Knicks during Round 2 Game 2 on May 7, 2025 at TD Garden in Boston, Massachusetts. Brian Babineau, NBAE via Getty Images/AFP

NEW YORK -- The NBA champion Boston Celtics are in unfamiliar territory, heading to New York down 2-0 after surrendering 20-point leads to the Knicks in each of their first two Eastern Conference semi-final series games.

The Game 1 defeat was bad enough -- putting the Celtics down in a series for the first time since 2023.

Then came Wednesday's near-replica collapse against a Knicks team they beat four times in the regular season.

"In two games, we're up 20 points and somehow, not end up with wins, it's inexcusable," said Jaylen Brown. "But we're going to learn from it. We're going to respond."

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The Celtics, led by Brown and Jayson Tatum, went 16-3 in last year's playoffs on the way to the club's NBA record 18th title.

On Wednesday they missed 14 of their last 15 shots from the field. Long reliant on the three-pointer, they missed 45 from beyond the arc in game one and missed 30 of their 40 attempts in game two.

Tatum is 12 for 42 over the first two games. His eight turnovers include Mikal Bridges's swipe of the ball in the final seconds that sealed the Knicks' 91-90 victory on Wednesday.

"I take full ownership for the way that I've played in this series," Tatum said Thursday. "Can't sugarcoat anything. I need to be better. And I expect to be a lot better."

Tatum said it was time for the entire Celtics team to "look in the mirror" as they head to Madison Square Garden, where the cheapest seats for Saturday's had surged to over $600 on ticket resale sites including StubHub, Gametime and TickPick.

StubHub had tickets priced at $626 and TickPick had their lowest-priced seats at $795 on Thursday.

Courtside seats were being offered at upwards of $40,000 according to Gametime on Thursday.

Knicks fans willing to shell out might be aware that only five teams have rallied to win a best-of-seven NBA playoff series after dropping the first two games at home.

But the Celtics have the credentials to join that list. They haven't lost three games in a row since the 2023 Eastern Conference finals -- when they dropped the first three games before falling in seven to the Miami Heat.

This season they have been an impressive 33-8 on the road compared to 28-13 at home.

"In a way, it kind of takes all the pressure off of us," said center Kristaps Porzingis, who has been slowed in the first two games by the lingering effects of illness.

"If you check the odds, maybe the Knicks are the favorites now to win. We were expected to win, so for us to be in this hole with our backs against the wall, we have nothing to lose," Porzingis said. "There's a lot of basketball yet to play. Let's see where this goes."

Added Tatum: "It's not about our season being two games from over.

"That hasn't crossed any of our minds. We've got a game on Saturday at 3:30 that should be a lot of fun. If you're a competitor, you should really look forward to that moment."

© Agence France-Presse