If it is not retired, it is fair game in my opinion.
Randy Moss could have been the best of all time had he found the right attitude on and off the field. I thought I would find out why he did not play his entire career there. After all, if they are going to retire his number surely he was a lifer.
He played his first 7 years with the Vikings and they TRADED him to the Raiders. At football.about.com from 2/23/2005 there is the following: "After weeks of speculation, the Minnesota Vikings have agreed to trade enigmatic wide receiver Randy Moss to the Oakland Raiders, a franchise that has been the eventual destination of many NFL malcontents and misfits over the years." Maybe he should stop and think how little the Vikings thought of him at the time that they would be willing to trade his all-worldliness to the Raiders for a middle linebacker (Napoleon Harris) and 2 7th round draft picks.
After stints at Oakland and New England, he returned to the Vikings where he was WAIVED him.
If they did not value his services worthy of keeping him in his prime, what's to say they value his services enough to retire the jersey. Mr. Moss should move on.