Jayson Tatum had 22 points, nine rebounds and seven assists, Payton Pritchard scored 23 points and the Boston Celtics easily got their first win in the Eastern Conference semifinals by routing the New York Knicks 115-93 on Saturday in Game 3.

The Celtics went 20 for 40 from 3-point range after going just 25 for 100 in their two losses in Boston, when they blew 20-point leads in the second half of both games. They went ahead by 31 in this one and there was never anything resembling a comeback for the Knicks.

Tatum, an All-Star who shot just 12 for 42 overall in Boston, and Pritchard, the NBA Sixth Man of the Year, both made five 3s.

Jaylen Brown scored 19 points and Derrick White had 17 for the Celtics, who will try to tie the series Monday night in Game 4 before returning to Boston for Game 5 on Wednesday.

Jalen Brunson scored 27 points and Karl-Anthony Towns had 21 points and 15 rebounds for the Knicks, who blew a 2-0 lead in this round last year and are still seeking their first conference finals appearance since 2000.

Boston made more 3-pointers than any team in NBA history during the regular season, when it swept all four meetings against New York. But the Celtics were ice cold to open this series, starting with an NBA playoff-record 45 misses in Game 1.

They made their first four 3-point shots in a blistering start Saturday and never really slowed down. They finished 6 for 7 behind the arc en route to a 36-20 lead, their highest-scoring first quarter of the postseason, quickly taking the energy out of a crowd where some fans paid more than $600 per ticket to be in the arena with the celebrities for one of the biggest games the Knicks have played in the 2000s.

Tatum and Pritchard hit consecutive 3s for a 55-33 lead with 4 1/2 minutes remaining in the half, and Boston took a 71-46 lead to the locker room.

New York was 5 for 25 behind the arc and shot 68.6% on free throws - though that was mostly because Mitchell Robinson went 4 for 12 as the Celtics fouled the poor free throw shooter intentionally.