Broncos wide receiver Aaron Burbridge is retiring, a source tells Field Yates of ESPN.com (on Twitter). Burbridge, once a standout player at Michigan State, was pushing to make the roster as a special teams player.
Burbidge notified the Broncos on Wednesday morning he planned to retire, and Mike Klis of 9News notes (via Twitter) the team waived him. 
Unfortunately, injuries have marred the 25-year-old’s career. After entering the league as a sixth-round pick of the Niners, he was kept off the field for much of the last two years. In his rookie year, Burbridge managed seven catches for 88 yards.
Without the wide receiver, the Broncos have a vacant spot to fill on their 90-man roster.