Brevin Pritzl scored 15 and Brad Davison added 14 points for the Badgers (11-15, 4-9 Big Ten). Happ, who averages 17.4 points per game, also had six rebounds, eight assists, two steals and three blocks.
Frazier hit a 3-pointer to tie it with 11 minutes to play before Wisconsin used an 11-2 run to take a 63-54 lead six minutes later after Davison made a 3. Pritzl scored 10 points from there, including two long 3-pointers from the left wing, to seal it.
The Badgers shot 53 percent from the field, including 8 of 15 from 3-point range, and had 20 assists on 25 field goals. The Illini were 21-of-55 (38 percent) shooting.
Wisconsin’s 13-game win streak over Illinois is the longest win streak in series history. The Illini last defeated the Badgers on Jan. 2, 2011 in Champaign. …Neither team has played well in Big Ten conference play, and things don’t get easier. Three of Wisconsin’s five remaining regular-season games are against currently ranked opponents; No. 20 Michigan, No. 3 Purdue and No. 4 Michigan State. Illinois has six remaining games, including at Michigan State and at home against the Boilermakers.
Wisconsin begins a three-game home stand against Michigan on Sunday.
Illinois hosts Penn State Sunday, ending a stretch of five out of six games at State Farm Center.