The Chicago Bears are fearful linebacker Roquan Smith's pectoral injury may be serious.
Smith, the eighth overall pick in the 2018 NFL Draft, left Chicago's 31-24 win over the Dallas Cowboys in the first quarter after trying, unsuccessfully, to stop Ezekiel Elliott scoring a touchdown.
It was the Bears' third straight victory, keeping them in the mix for a playoff berth in the NFC, but head coach Matt Nagy hinted Smith could be missing for his team's final three games.
The linebacker had arguably the best game of his career in Week 13, having contributed 16 tackles and two sacks in the Thanksgiving win over the Detroit Lions.
"He has a pec[toral injury]. We'll get more details here in the next couple of days," Nagy told reporters.
"It doesn't look real good for him.
"It could be a big loss. The way that Roquan has been playing the last couple of weeks, flying around, making plays, you just love that confidence that he's bringing to the defense.
"The depth that Ryan [Pace, Bears general manager] and his guys have created on this roster allows someone like Kevin Pierre-Louis to step up and make plays. You feel bad for Roquan but we know we have guys that can fill in."
The Bears season appeared to be heading south when they were beaten by the Los Angeles Rams in mid-November to drop to 4-6.
However, much-maligned quarterback Mitchell Trubisky's recent good form has helped to turn their campaign around, with the 25-year-old throwing six touchdowns and just two interceptions over the past two weeks.
"Right now, the identity between the defense and offense, it doesn't feel like one of those deals where if we don't hold them to under 14 points, we don't have a chance to win," Nagy added.
"We feel like we're finally, in all three phases, working together.
"When you have that, you know going into most games you're going to have a chance to win."