The Denver Broncos could be facing a huge loss after top wide receiver Emmanuel Sanders went down with a left leg injury during the team's practice on Wednesday.
Coach Vance Joseph said the injury "does not look good" and Sanders will undergo further testing to determine the severity.
According to ESPN, the belief is Sanders tore his Achilles.
"He's having an MRI in the next hour or so, we'll know if it's torn or not," Joseph told reporters after practice.
"Obviously that's huge for us. We lost Chris Harris last week. That's two Pro-Bowl calibre players and two leaders."
Sanders was helped off the field and did not put any weight on his left leg as he was taken into the locker room for further evaluation, according to The Gazette of Colorado Springs.
The injury happened early in practice as he went down during passing drills. Sanders slipped when he was making a cut on a short route and there was not anyone around him, 9News reported.
"It's tough," Broncos quarterback Case Keenum said, via ESPN.
"You don't really replace guys. Emmanuel is one of the best guys I've ever worked with. It surpassed all my expectations, far and away."
According to NFL Media, Denver claimed former Bills receiver Andre Holmes later on Wednesday.
Sanders has made a significant impact this season for the Broncos' offense as he has 71 receptions, almost twice as many as his nearest team-mate, for a team-high 868 yards and four touchdowns through 12 games.
The Broncos (6-6) have climbed back into the AFC playoff discussion with a three-game winning streak that they put on the line against the 49ers in San Francisco on Sunday.
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