Only a handful of Broncos were not present for the team's first organized team activity of the offseason, which is considered a voluntary session. DT Derek Wolfe couldn't practice because the University of Cincinnati is still in its spring quarter. LB D.J. Williams missed the session because his DUI trial got under way. DT Ty Warren didn't practice, as he hasn't been at team headquarters recently because of a contract impasse. K Matt Prater, who hasn't signed his franchise tender, was also absent.