Terrence Shannon Jr. scored 12 of his 16 points in overtime, including the tiebreaking 3-pointer with 3:34 remaining, and No. 17 Illinois rallied to hand second-ranked Texas its first loss of the season, 85-78 on Tuesday night in the Jimmy V Classic.

Jayden Epps added 11 points, including the final five points of regulation — a 3-pointer with 35 seconds left and two tying free throws with 8 seconds remaining. Epps then blocked Marcus Carr’s jumper in the lane just before the buzzer to force overtime in an entertaining showdown at Madison Square Garden.

Matthew Mayer, who faced Texas several times at Baylor, tied a career high with 21 points as he made his first seven shots and finished 8 of 10.

Shannon, who missed eight of nine shots in regulation, took over in the extra period to help Illinois (7-2) beat a ranked foe for the second time this season. He opened overtime with a jumper after Carr was called for traveling and then hit an open 3 from the right wing over Brock Cunningham for a 73-70 lead.

Shannon converted a reverse layup and finished a three-point play to make it 77-70 with 2:16 left. Carr hit two free throws to get Texas within one with 1:28 remaining.

Jayden Epps made a layup, RJ Melendez sank two free throws to put Illinois ahead by five, and Shannon made two free throws with 27.7 seconds left.

Timmy Allen scored a season-high 21 points for Texas (6-1), which failed to open 7-0 for the first time since 2014-15. Tyrese Hunter added 10 points but Carr was held to nine points on 3-of-14 shooting as Texas had 12 shots blocked and shot 42%.

Illinois hosts Penn State in its second Big Ten game on Saturday.