MANCHESTER, N.H. -- Brad Stevens will celebrate his first NBA coaching victory when it counts.
Boston was winless in its first three exhibition games under Stevens, who was hired away from Butler to take over the storied franchise at the age of 36.
"If I'm not going to count those last three, I can't count this one I guess," Stevens joked.
The Celtics scored at least 24 points in every quarter, shot 54 percent and -- most importantly -- looked little like the team that lost to Philadelphia 97-85 the night before.
"We got the ball up the floor. We played with good pace. I just thought we didn't labor as much offensively as we did yesterday," Stevens said.
The Celtics capitalized on a short-handed version of the Knicks, who were playing their third game in four nights and rested Carmelo Anthony and most of his veteran teammates.
Rookie Kelly Olynyk had 15 points and six rebounds for the Celtics, who scored the first 10 points and never trailed.
Boston started the third quarter with a 20-5 run against a JV version of the Knicks, who also played the night before.
"I know it's a back-to-back and I'm playing young players, but again you've got to be proud to wear a Knick uniform and tonight was an embarrassment," coach Mike Woodson said. "Whoever we put out there, we should be able to compete."
Olynyk, a 7-footer from Gonzaga drafted by the Celtics with the 13th overall pick, also had six rebounds, three steals and a block as the Celtics won a "home" game played about 50 miles north of Boston.
The Celtics outrebounded New York 45-34.
"I think it eased Coach Stevens' nerves a little bit. I know he's not used to losing," said Jared Sullinger, who scored 12 for Boston. "We have a blueprint now. You've got to follow the blueprint to success and understand that the way we played today should be the way we play all the time."
MarShon Brooks scored 11 of his 13 points in the second half as the Celtics let their younger players finish off the rout.
The Toronto Raptors selected Utah center Jakob Poeltl with the No. 9 overall pick of the 2016 NBA draft on Thursday night.
The Sacramento Kings selected Washington power forward Marquese Chriss with the No. 8 overall pick of the 2016 NBA draft on Thursday night.
The Milwaukee Bucks chose 19-year-old Sudan native Thon Maker of with the No. 10 overall pick on Thursday night.