Lock (thumb) returned to practice Tuesday, meaning he's one of the Broncos' two players designated to return from IR, Jeff Legwold of ESPN.com reports.
This is Lock's first time on the practice field since Aug. 19, as he's rehabbed a sprained thumb in his throwing hand. The Broncos are currently deploying Brandon Allen under center with Joe Flacco (neck) on IR, and they have until Week 14 against the Texans to activate Lock. Coach Vic Fangio has already named Allen the starter for this Sunday's matchup against the Vikings, but Lock -- a rookie second-round pick -- could serve as his backup if he's activated.