The Bulls don't have size, speed or anything else considered glamorous in the NBA.

Going back to last season, however, they have been characterized by working-class grit. Among Chicagoans, that goes a long way.

At this point, they are in danger of losing their identity. For the second time in three games, their hustle and heart eluded them.

Instead of taking advantage of a depleted Charlotte Bobcats roster or keeping up the spectacular shooting display that wiped out the Boston Celtics on Saturday night, the Bulls looked bored and befuddled Tuesday night in their 105-92 loss before a sellout crowd of 21,768 at the United Center.

"We didn't have the effort needed to win," Chris Duhon said. "We got what we deserved."

Bulls coach Scott Skiles made similar comments Friday night after the Pistons thrashed the Bulls. Losing to Detroit, maybe the best team in the league, is one thing. Losing to a second-year club that came in with only seven victories, needs an explanation. The Bulls had few answers.

"It was obvious they outplayed us from beginning to end," Skiles said.

The Bobcats (8-18) ended their winless streak against the Bulls at five games. Fans who left early missed nothing except uninspired Bulls basketball as the club dropped to 5-6 at home.

"We're not good enough to have that," Skiles said.

The Bulls (12-12) had a chance to make headway in the post because Charlotte's Emeka Okafor, last season's NBA Rookie of the Year, was out with a sprained right ankle.

"They're missing a big-time shot blocker right now," Skiles said.

Gerald Wallace had no trouble filling in for Okafor, collecting five blocks in addition to his 19 points and eight rebounds.

"I can't recall a game where he hasn't killed us," Skiles said.

Between starters Michael Sweetney and Tyson Chandler and reserve Othella Harrington, only Harrington capitalized on the absence of Okafor. Harrington finished with 16 points, at times using slick post moves Bulls frontcourt players have displayed rarely this season.

Sweetney had some success, scoring 12 points, but struggled with fouls. Chandler also had foul trouble, getting two in the first three minutes. He played only 21 minutes overall.

"I felt Mike potentially could have had a big night, but he couldn't stay on the floor," Skiles said.

Harrington and Duhon each scored 16 points to lead six Bulls in double figures.

"Duhon had a good game," Skiles said. "Other than that, we were hard-pressed to challenge that kind of play."

Okafor was one of four injured Bobcats and is perhaps their most productive player at 12.9 points and 10.1 rebounds per game. Even without Okafor, the Bobcats beat the Bulls on rebounds, 39-35, mostly behind Primoz Brezec's 10 that complemented his 13 points.

Going with a small lineup worked for Charlotte, especially because rookie Raymond Felton had the look of an All-Star for the Bobcats, which probably was more a condemnation of the Bulls. Felton finished with a career-high 21 points on 8 of 13 shooting. He also had six rebounds, five assists, two blocks and only one turnover.

Charlotte's Brevin Knight, the former Stanford star who had been listed as questionable because of a right forearm contusion, had 20 points and 10 assists.

mxgarcia@tribune.com