PRINCETON, N.J.—After defeating Penn on Friday night, the No. 21/25 Harvard men’s basketball team was expected to complete its first road sweep of the “Killer P’s” since 1985 at Princeton on Saturday night.

And for much of the game, it looked like the heavily favored Crimson was poised to do just that, leading with less than 10 minutes to play.

But junior Kyle Casey missed four of five free throws down the stretch, and the Tigers closed the game on a 28-18 run to grab a 70-62 win in front of a packed house at Jadwin Gymnasium.

The Crimson surrendered 48 second-half points, a season high, as the Tigers connected on 15 of 24 (62.5 percent) attempts from the field in the frame.

“Certainly it was a tough, tough loss for us,” Harvard coach Tommy Amaker said. “I told our kids that I thought Princeton deserved to win. I thought they played an exceptional second half.”

Harvard (21-3, 7-1 Ivy) struggled to contain Princeton (13-10, 4-3) forward Ian Hummer in the post all night, as the junior led the Tigers with 20 points, nine rebounds, and six assists.

Offensively the Crimson turned in one of its worst shooting performances of the season, going five of 18 from beyond the arc and getting to the free-throw line just 11 times, matching its second lowest total of the season.

Harvard’s offensive woes intensified down the stretch, as the Crimson went one of seven from deep and three of seven from the charity stripe in the final 10:44 of play.

“I was disappointed in our inability to make the plays necessary in the second half offensively,” Amaker said.

But perhaps more devastating to Harvard’s hope of grabbing its first win at Jadwin since 1989 was its inability to come up with stops late in the game. After holding the Tigers to 38.5 percent shooting in the first half, the Crimson allowed Princeton to connect on eight of its final 10 attempts from the field.

“We found something that worked on offense, and we just kept going to it,” said Princeton’s TJ Bray, who scored seven points in the game’s final 8:44 and finished with 12 points and four assists on the night. “Harvard likes to get up and try to get in the passing lanes, and that’s really when our back-door offense is huge for us.... A lot of stuff was open back door tonight.”

Bray put Princeton ahead by two, 48-46, with 5:14 to play after spinning baseline and sticking a short jumper.

Casey (12 points) attacked the basket on the other end, nearly converting an and-one layup, but the ball rimmed out, and the junior went to the line with two shots.

Casey, a 76.6 percent career shooter from the stripe, went one of two, pulling the Crimson within one, 48-47.

On the ensuing Tigers’ possession, Casey committed a foul on Hummer as the forward drove to the basket, and Hummer made Harvard pay, knocking down both attempts.