The Indianapolis Colts wide receiver, who was drafted in 2001, has over 13,000 receiving yards and 80 touchdowns during his career for the AFC South side.
The team's head coach told the Colts' official website: "He takes a beginner's mentality every year that he shows up to training camp. All the great ones do that. That's what he's done.
"Every year he comes in, it's like starting over. He's got his iPad out, he's got his notepad and he treats it like his rookie year. He takes no days for granted and he takes no practices for granted.
"He came in from day one you could see the talent was there, but his work ethic, his passion for the game, the way he studied and the time that he put in, things that he sacrificed, it was real evident early on that he was."
The Colts play the San Diego Chargers tomorrow.