Mike Klis of 9News also reported on the injury and noted that he watched it occur:
It's a serious injury for Sanders, who previously dealt with nagging ankle issues throughout the 2017 season.
Because of those recurring woes, he was limited to 47 receptions for 555 yards and two touchdowns across 12 games.
Now in his fifth year with the Broncos, Sanders has bounced back and logged 71 catches for 868 yards and four scores as Case Keenum's favorite target and the team's leading receiver.
Provided the Achilles injury is confirmed and Sanders misses the remainder of the season, Denver will be forced to turn to rookie Courtland Sutton as the No. 1 wideout following the trade of Demaryius Thomas to the Houston Texans.
The Broncos will also have to lean more heavily on rookie DaeSean Hamilton, Tim Patrick, River Cracraft in addition to the newly acquired Holmes.
Hamilton, Patrick and Cracraft have combined for just nine receptions this season.
Look for the Broncos to lean heavily on Phillip Lindsay and the running game as they attempt to beat the San Francisco 49ers, push their record to 7-6 and remain in the thick of the AFC wild-card race on Sunday.