CHAMPAIGN, Ill. -- Ethan Happ scored 27 points on 12-of-20 shooting to lead Wisconsin to a series record 13th straight win over Illinois, 78-69 Thursday at the State Farm Center.
The Illini last defeated the Badgers on Jan. 2, 2011, in Champaign.
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.
"Ethan (Happ) did a good job for us tonight," Wisconsin coach Greg Gard said. "When Illinois puts that kind of pressure on you, you have to be able to find the open man. Ethan had eight assists for us and was our playmaker and point scorer. He found who he needed to with the ball. He's a pretty unselfish player."
Trent Frazier scored a career-high 32 points for the Illini (12-13, 2-10), and Leron Black added 13 points and 11 rebounds for Illinois.
"I just had a flow going tonight," Frazier said.
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.
"You have to give Trent credit," Gard said. "He made some tough, tough shots there at the end."
First-year Illinois coach Brad Underwood said Wisconsin's use of several ball handlers made defending the Badgers hard. "They are certainly a non-conventional team."
Wisconsin led 36-33 at the half.
"It's not been easy for us," Gard said. "We're a young team and we are learning and growing with each game. I think the guys showed more maturity tonight down the stretch, even though Trent (Frazier) kept them close."
The Illini were 21-of-55 (38 percent) shooting.
"It's frustrating. But tonight it was just a really, really good player (Happ) having his way with us," Underwood said. "We don't the size to deal with that."
BIG PICTURE: 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.
HIGHLIGHT REEL: Frazier's three long 3-pointers fired up the Illini crowd, while Pritzl quieted it with two from beyond the stripe.
UP NEXT: 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.