For the sec­ond time in three days, the Bron­cos saw one of their most impor­tant play­ers injured in prac­tice when receiv­er Court­land Sut­ton was unable to fin­ish Thursday’s work­out because of a shoul­der issue.

Sut­ton was diag­nosed with a sprained AC joint, where the col­lar­bone meets the shoul­der blade, accord­ing to a source, who added that Sut­ton is day-to-day and inter­nal­ly, there was a “sense of relief,” that it wasn’t a more seri­ous injury.

Sut­ton was injured on a routes-vs.-air (no defend­ers) drill dur­ing prac­tice when he reached for a pass and fell awk­ward­ly on his side.

On Tues­day, out­side line­backer Von Miller sus­tained an ankle ten­don injury that could keep him out the entire season.

Sut­ton, in his third sea­son, was named to the Pro Bowl last year after lead­ing the Bron­cos with 72 catch­es for 1,112 yards and six touchdowns.

If Sutton’s play­ing time Mon­day is lim­it­ed or he is inac­tive, the Bron­cos will have to lean on first-round pick Jer­ry Jeudy as well as sec­ond-round pick KJ Ham­ler (whose ham­string injury lim­it­ed him in prac­tice Thurs­day), Tim Patrick and Dae­Sean Hamilton.