It's been a long time, but I think I need to break down and buy an NFL jersey. I have not had an NFL jersey for over 10 years. I had an Emmitt Smith jersey back when I was a teen, and it served me well. I do have a USC no. 3 jersey, which represented Carson Palmer (without his name ont he back to be compliant with NCAA rules). I like to crack that jersey out for big games.... well for any game that USC plays in that I watch at home. Jerseys are a great way to support your team, and a jersey carries some power when you play pick up football games.
A few years back, my friends and I played games versus my uncle and his friends. There was an average age difference of about ten years. The older guys used about every dirty trick in the book, and their strength to be physical and knock us around. We countered with a no huddle offense to tire them out, and a zone defense that confused their passing game. By the end of the games, they were usually dead tired. Except for two guys. One was my uncle who wore a Dick Butkus jersey every game, and the other was a dude we called "Marshall Faulk". His name was Rick, but he went by Marshall on the turf, because despite his age, he was the 2nd fastest guy on the field. He wore a ratty looking Faulk Rams jersey, but it proved his point of fandom and that he meant business.
As a Cowboys fan, I'd like to go with a current player, but the pull of a legend jersey is strong. Dallas is incredibly smart, and they have the rights to the older players' name/jersey sales. The team sells replica throwbacks in their online store. For $75, a person can grab a Staubach or Dorsett jersey, and during the regular season, jerseys of many more "Legends" are available. My first instinct would be to get an Aikman or Staubach jersey. This way, I can't buy the jersey of a player and watch him leave in 3 years in free agency. I might grab a Staubach jersey and a DeMarcus Ware jersey, as the Cowboys have him locked up for 3 more years, and they will most likely resign him. The Staubach jersey is for a lifetime, and the Ware jersey can be for now.