After praising seldom used reserve Mike Shaw's effort, Groce had little else positive to say about the way Illinois face-planted on the Kohl Center court Saturday with a 74-51 loss to the Badgers.
The loss was a fourth in six games for the Illini (14-4, 1-3 Big Ten), but this one irked the coach enough for him to reevaluate every player in terms of toughness and consider lineup changes.
"I thought (Wisconsin) dominated every facet of the game," Groce said. "Their competitive spirit was better than ours. That's unacceptable."
Wisconsin burst to a 14-0 lead that set the tone for the lopsided affair.
No. 12 Illinois shot only 26.1 percent in the first half and 35.3 percent for the game, scoring a season low in points. The Illini trailed by 28 points early in the second half after falling behind 39-19 at halftime.
Groce said he can live with execution errors.
What ruffled him most was the team's blase approach.
The Illini were outrebounded 43-24 as the Badgers grabbed 18 offensive boards. Wisconsin (12-4, 3-0) outscored Illinois 23-11 on second-chance points, and center Jared Berggren scored 15 points to go with 12 rebounds.
"I thought we bailed out on charges," Groce said. "I didn't think we had a physical disposition about us on the glass. How do you play the No. 1 ranked team (Minnesota) in offensive rebounding Wednesday and get 74 percent back and get that kind of effort on the glass today? It's in there. We didn't have it today."
Groce took the blame and shared it with the team's captains.
"Nothing went right at all," said guard D.J. Richardson, who scored a game-high 16 points. "We played sluggish. We just have to get a better start. We have to play every game like we're the underdogs. We went into this game like we were going to win. We kind of went through warm-ups casual."
Wisconsin shot 53.3 percent in the first half and finished the game making 49.1 percent of their shots.
The Illini made the Badgers, who had just come off a 47-41 eyesore victory against Nebraska, look like offensive machines. Wisconsin made 10 of 23 3-pointers.
Illinois forward Tyler Griffey, who shot just 1 of 6, left the game briefly with a gash over his eye. He returned to the game with stitches.
Guard Brandon Paul was held to 1 of 11 shooting. He scored eight points, making this the only time this season he has failed to reach double digits.
Shaw grabbed three rebounds, scored two points, recorded a steal and exemplified hustle in 19 minutes.
"Mike Shaw played like his head was held under water," Groce said. "That's what I'm looking for."