The Bears on Wednesday placed left guard James Daniels on injured reserve and promoted offensive lineman Sam Mustipher to the active roster.
Daniels injured his pectoral muscle in last Thursday night's 20-19 win over the Buccaneers. Since being selected by the Bears in the second round of the 2018 draft out of Iowa, he has played in all 37 games with 31 starts.
Daniels started the final 10 games of his rookie season in 2018 at left guard. He opened the first eight contests in 2019 at center—flip-flopping with Cody Whitehair—before the two returned to their previous positions, where they have remained.
"It's heartbreaking," offensive line coach Juan Castillo said of the injury to Daniels. "I could see it in his eyes. It's sad because this is a young man who's been working hard, playing better. He's got a big heart, [he's a] hard worker, everybody likes him in the room. It hurts to see something like that happen.
"The positive thing is he's going to get back at full strength. He's 23 years old, so he has a great future ahead of him. Those are things you have to look at when you have a setback like that, look at the positive things. That's what we're trying to do with him and talking to him."
Mustipher signed with the Bears last year as an undrafted free agent from Notre Dame. He spent his entire rookie season and the first five games this year on the team's practice squad.