ENGLEWOOD, Colo. -- Broncos wide receiver Tim Patrick was carted off the field Monday with a left leg injury almost a year after he tore his right ACL at training camp.

Coach Sean Payton told reporters the team fears that Patrick suffered an Achilles injury.

Patrick, 29, was embarking on a comeback after missing all of last season.

He was participating in a 7-on-7 drill with the Broncos in full pads for the first time and his left leg buckled as he pushed off to run a route. He yelled out in pain and threw his helmet as Payton, quarterback Russell Wilson and receiver Courtland Sutton were among the first to rush over to him.

He was helped onto a cart and taken inside team headquarters as the crowd of about 3,000 fans fell silent.

Patrick was the team's No. 1 receiver going into last season when he tore his right ACL in a noncontact drill Aug. 2.

He was a projected starter again this summer in a crowded wide receiver room that also features Jerry Jeudy, Sutton, rookie Marvin Mims Jr., Brandon Johnson, Marquez Callaway and Lil'Jordan Humphrey, among others.

The Associated Press contributed to this report.