"Kurt Warner, who retired last week from the National Football League after 12 seasons, said his experience in training camp in 1994 with the Green Bay Packers played a crucial role in his unusual development into a star quarterback.

Warner, who was interviewed Tuesday on ESPN Radio's "Mike and Mike in the Morning" show, was asked by Mike Golic when he realized after his college career at Northern Iowa that he was good enough to compete in the NFL.

"Actually, when I went to Green Bay," Warner said. "I was competing against Brett (Favre) and Mark Brunell and Ty Detmer. That was probably the most confident I was that I could play at this level. I think we all believe it when we are playing in college. You are like, 'I can play at that level, no problem. It's just a little step up.' But I actually went there and competed against those guys. You could tell how special Brett was going to be at that time. Obviously, I knew Mark and how talented he was."