Toronto Raptors coach Dwane Casey said his all-star point guard will travel with the team to Chicago, but the chances of him playing are "50/50."
"He's sore as we knew he would be, so we'll find out, we'll see how he is (Friday)," Casey said. "He's moving good, but again he's just sore. No structural damage, he's sore."
Lowry left Wednesday night's 105-100 win over the visiting Timberwolves with a back contusion, suffered when he went up for a layup and came down on the leg of Minnesota's Gorgui Dieng.
Lowry, who's averaging 18.1 points, 6.9 assists and 4.6 rebounds a game, walked gingerly out of the Raptors' practice on Thursday morning and didn't speak to reporters.
The all-star missed three games earlier this season for what the team called "rest," and upon his return, was playing some of his best basketball of the season. Lowry recorded a triple-double — 20 points, 11 rebounds, 10 assists — in Toronto's 117-98 win in Indiana on Monday.
"It would be tough (to play the Bulls without Lowry)," said Raptors forward Patrick Patterson. "Of course, we'd rather have Kyle out there than not out there but at the end of the day we want him healthy for the playoffs. We don't want him hurt, we don't want him to have any nagging or lagging injuries or tolls on his body once playoffs start. If he needs the time off, better to take it now than in the playoffs.
"It will just cause other people to step up, more guard rotations, more people playing bigger minutes, just more pressure on us to get a win."
The Raptors are in third place in the Eastern Conference standings, half a game up on Chicago.
Note to readers: This is a corrected story. The first name of coach Dwane Casey was misspelled in a previous version.