Sometimes, youth inspires performances like the Boston Celtics had in their first preseason game against NBA competition. But there was no encore Friday night.

A slow start and sloppy play down the stretch doomed the Celtics in their 101-95 loss to the New York Knicks at Madison Square Garden.

Isaiah Thomas (13 points), Tyler Zeller (12), Evan Turner (11) and James Young (10) led the way for Boston offensively. New York’s Derrick Williams led all scorers with 19 points.

But those weren’t the stats that made the difference. Instead, it was the Knicks’ turnover advantage (20-9), and their performance from 3-point range (48 percent) that made the real impact in this one.

STARTING FIVE
Isaiah Thomas, Avery Bradley, Jae Crowder, David Lee, Amir Johnson

STAR OF THE NIGHT
Young had one of his best games in a Celtics jersey, even if he did most of his damage in the fourth quarter. He was one of four players who finished in double digits in scoring for Boston despite playing just 16 minutes.

He was the best offensive player for the Celtics in the final 12 minutes, which is a good sign for his development after spending most of last season with the Maine Red Claws in the Developmental League.

FEELS GOOD TO BE BACK
Bradley made an immediate impact in his return to the C’s starting five after sitting out Wednesday’s game against the Brooklyn Nets.

Bradley finished with seven points, eight rebounds and three assists in 21:36 minutes. All eight of his rebounds came on the defensive end, where he also came up with a steal.

MORE PRESEASON FLAGRANT FOULS
Things got a bit chippy between the two teams near the end of the third quarter.

Jared Sullinger, who had a quiet game up to that point, was hit hard by Kyle O’Quinn as he went up for a layup. Initially, Jonas Jerebko was the one who got a technical for walking toward his injured teammate, but the refs reversed that decision and gave O’Quinn a flagrant 1 foul instead.

TWEET OF THE NIGHT
Brad Stevens got a technical. We repeat, Brad Stevens got a technical.

UP NEXT
The Celtics will play their first home preseason game Monday when they face the Brooklyn Nets at TD Garden. Game time is scheduled for 7:30 p.m. ET.

Thumbnail photo via Mark J. Rebilas/USA TODAY Sports Images

Thumbnail photo via Boston Celtics guard James Young (13) against the Phoenix Suns at US Airways Center. The Celtics defeats the Suns 115-110.