Dylan Harper racked up 28 points, six rebounds and five assists in his return from a two-game injury absence and Rutgers blew a 17-point lead before coming back to upset No. 23 Illinois 82-73 on Wednesday in Piscataway, N.J.

Ace Bailey added 18 points and 11 rebounds and Jeremiah Williams scored 13 for Rutgers (12-11, 5-7 Big Ten). After squandering a major advantage, the Scarlet Knights used a 15-5 run to regain control in the home stretch.

They went 28-of-34 from the free-throw line, including a 11-of-12 performance from Harper, who suffered a high ankle sprain Jan. 20 and tried to play through it before missing a pair of games.

Will Riley led Illinois (15-8, 7-6) with 18 points and six assists off the bench, Ben Humrichous scored 14 points and Morez Johnson Jr. chipped in 11. The Fighting Illini lost for the fifth time in eight games despite outshooting the Scarlet Knights 41.5 percent to 40.7 percent from the floor.

Illinois trailed by 11 early in the second half but used a 15-3 stretch to climb back into the game. The Illini held Rutgers without a field goal for more than four minutes, and Humrichous’ jumper gave Illinois its first lead at 48-47 with 13:06 remaining.

Harper answered with his second triple of the night, but the Illinois offense kept flowing. Kasparas Jakucionis made a game-tying layup and Riley stroked go-ahead 3s at 53-50 and 60-58 as the lead swung back and forth.

Rutgers ran off seven straight points, capped by Harper’s third 3-pointer and Jamichael Davis’ foul shot, for a 67-62 lead with 6:15 to go. When Williams added an acrobatic floating hook shot, it was 71-65, Rutgers’ largest lead since Illinois rallied.

The Illini missed eight of their final 10 shots.

It was all Rutgers early. Stellar defensive plays led to fastbreak buckets for Davis and Bailey for a 13-4 lead, and a 10-0 Rutgers run soon made it 23-6 with 9:43 left in the half.

Illinois, meanwhile, made 3 of 17 from the field to start the game and experienced multiple lengthy field-goal droughts. The Illini were down 27-11 after Harper swished a 3-pointer from the left wing.

Riley scored seven points in the final 4:08 and Humrichous canned a 3-pointer to trim the deficit to six before Rutgers took a 37-29 lead into halftime.