Tracy Abrams scored 13 points and Rayvonte Rice was held to eight for the Fighting Illini, who were upset 49-43 by in-state rival Northwestern. Illinois (13-4, 2-2 Big Ten) has lost two straight after four consecutive wins, and once again its offense struggled, hitting just 28.1 percent of its shots.
"I felt like we did not make enough plays on offense. I didn't feel like we were nearly aggressive enough. I thought we were way too tentative offensively," Groce said. "We're going to have to figure that out pretty quickly. I feel like it's been that way now for a couple games."
Rice, who entered as the conference's leading scorer at 18.8 points per game, didn't get his first basket until there was 8:39 left in the second half. The redshirt junior guard was 2 of 11 from the floor and missed all five of his first-half shots. He had scored 19 points on 7-of-21 shooting in a 95-70 loss to No. 4 Wisconsin in Madison on Wednesday.
During their loss to the Badgers—the Fighting Illini's most lopsided defeat of the season—they shot just 31.6 percent from the floor and had just Rice and Joseph Bertrand score in double figures. That didn't improve much Sunday, when Illinois made 18 of 64 shots.
"Shots didn't fall that guys normally make," Abrams said.
Meanwhile, Tre Demps and Northwestern made just enough.
Demps scored 11 points and made three late 3-pointers, cutting off an Illini rally. Drew Crawford added 14 points and JerShon Cobb had 11 for Northwestern (8-9, 1-3), which gave Northwestern coach Chris Collins his first conference win.
After leading by as many as eight in the second half, Northwestern allowed Illinois to tie the game at 27 on Kendrick Nunn's layup with 11:31 left. Demps, though, hit three 3-pointers in three minutes, the last giving Northwestern a 43-36 lead with 3:28 to go. Cobb's layup with 1:53 left gave the Wildcats a 45-36 advantage.
Illinois thought it cut the lead to 45-42 with 55.9 left, but Bertrand was called for charging, wiping out his basket. The Illini got to 45-43 when Rice hit a 3-pointer with 15 seconds left. Crawford hit two free throws with 14.3 seconds left, and Northwestern finished the upset.
"I've been at the gym all day for the last two days and I was just waiting for a good look. When I hit the first one I got a good rhythm going," Demps said. "But the main thing was that my teammates believed in me."
Collins never would have believed his team would score so little in his first conference win as a head coach.
"That was a special night for us. Obviously, thinking of getting my first Big Ten win I never thought my team would have only 49 points," Collins said. "I always liked to have 49 myself when I played."
Northwestern had lost four straight overall and three in a row in conference play, but snapped both streaks thanks to its defense. Following a one-point loss to DePaul on Dec. 27 to end nonconference play, the Wildcats lost by 27 to Wisconsin, 23 to Michigan, and 26 to Iowa before beating Illinois.
The Wildcats shot only 37.2 percent from the floor but that was enough to beat the Fighting Illini.
"This is the Big Ten," Abrams said. "You can lose to any team or you can beat any team in the Big Ten. One of the toughest conferences in the country."
Ranked for the first time since Jan. 14-20, 2013, Illinois got off to a slow start in the lone meeting between the in-state rivals this season.
The Illini shot 6 of 31 from the floor (19.4 percent) and missed all eight of their 3-pointers in the first half and trailed 22-15 at halftime. The 15 points were the Illini's fewest in a half this season and the second-fewest Northwestern has allowed over 20 minutes.
Northwestern couldn't pull away in the first half, shooting 33.3 percent. Despite that, it was still able to hold off Illinois.
"Let's give them a lot of credit," Groce said. "I thought they played really well on the defensive end and made it very difficult to score."