There are major questions about whether Chicago Bears starting wide receivers Brandon Marshall and Alshon Jeffery will play Sunday night against the San Francisco 49ers.

Both players were listed as questionable to play and one source said he was "75 percent" sure neither would play. In addition, receiver Josh Morgan is listed as doubtful on the injury report with a groin injury.

The Bears had just four receivers on their active roster before signing Josh Bellamy and Chris Williams off their practice squad Saturday. Veteran Santonio Holmes would start at one receiver spot if both Marshall and Jeffery are out. It is unclear who would fill the other spot if Morgan also is out Sunday, although the team spent extra time at Friday's practice working with Bellamy.

Marshall (ankle) and Jeffery (hamstring) were both injured in the Bears' Week 1 loss to the Buffalo Bills.

The Bears held out Marshall from Friday's practice, but he came out and participated during the walk-through portion. Jeffery practiced in a limited capacity and took part in some of the full team drills.

Information from ESPN.com Bears reporter Michael C. Wright was included in this report.