Derrick Rose visited a back specialist Monday as planned, and the Bulls received reasonably good news.
An MRI exam showed no structural damage, general manager Gar Forman confirmed. The problem is believed to be muscular, and Rose will continue to receive treatment. His status is day to day.
Rose has missed the past two games with back spasms and doesn't figure to play Tuesday night when the Bulls host Sacramento in their first game at the United Center in 18 days.
Back injuries can be unpredictable, so it's tough to put a time frame on when the Bulls' leading scorer will return. He said the back bothered him during most of the nine-game road trip, which concluded Sunday with a loss in Boston.
"Something just happened," Rose said Sunday, according to bulls.com. "I did not have any falls on my back. It's something I just woke up and my back was tight and I really can't get rid of it now."
Playing without one of their starters is something the Bulls are used to. Their projected starting lineup of Rose, Richard Hamilton, Luol Deng, Carlos Boozer and Joakim Noah has played together just five times in 30 games this season.
The Bulls haven't used those starters since Jan. 4 in Detroit.
Of those players, only Boozer has appeared in all 30 games. Hamilton has missed 19, Rose and Deng seven each and Noah one.
The most frequent starting lineup has Ronnie Brewer in place of Hamilton, and that group has gone 10-1. Without Rose, the Bulls are 5-2.
C.J. Watson has started the past two games in Rose's place. He scored 22 points against the Celtics but shot just 30 percent from the field in the past three games.
"We have a deep team," Rose said. "If one of us goes out another guy comes in and does the job. That's what makes us a special team. If I'm not playing, I don't have to worry about it because we have C.J. and J-Luke (John Lucas III) coming in and they play well under pressure."
The Bulls (23-7) still hold first place in the Eastern Conference, but their most recent victory over a team that currently owns a winning record was Jan. 13, the first time they played in Boston.
During the monstrous nine-game road trip, they beat six teams with losing records -- mostly by a wide margin -- while losing to Miami, Philadelphia and the Celtics.
After starting the season 6-1 against teams that are currently .500 or better, the Bulls have dropped five in a row. In the meantime, they've won 17 straight against teams that have losing records.
According to espn.com, the Bulls have played the second-softest schedule in the league, based on opponents' winning percentage.
As they approach the lockout season's halfway point, there is reason to question whether the Bulls really are the best team in the East. Do the injuries justify the lack of quality wins?
Time will tell, but not right away. After the long road trip, the Bulls play the next six at home but face just two teams with winning records, Boston and Atlanta.
Their schedule won't get tougher until Feb. 29, when they begin a trip through San Antonio, Cleveland and Philadelphia, followed by a home date with Indiana.
A win over Sacramento on Tuesday would clinch the Eastern Conference all-star coaching slot for Tom Thibodeau.