The Ravens got their roster down to 53 players Saturday, but their maneuvering is nowhere near done before next Sunday’s regular-season opener against the Denver Broncos. In fact, Sunday could be as busy as Saturday, with teams making waiver claims and assembling their 10-man practice squads. There also likely will be at least one move on the Ravens’ 53-man roster, as they are expected to put second-year defensive end Brent Urban, who had surgery to repair a torn biceps last month, on injured reserve with a designation to return. That will open one roster spot. Here are several questions the Ravens could address Sunday.