Although Robert Smith was dedicated to being a great football player, I'm not shocked at his decision to retire at age 28. As one of the NFL's brightest and most self-sufficient players, Smith never allowed his life to revolve around football.

Smith has always had options outside of football. After taking some time off to travel, relax and mend his body, he could go to medical school and become a doctor. Businesses could pursue him because he would be an excellent spokesperson. Smith is not afraid to try new things, and he is capable of making as much of a difference off the field as he did on the field with the Minnesota Vikings.

Knowing him as well as I do, I believe injuries played a large role in his decision to retire. After eight seasons, he probably had enough of the game's grind. He's a dear friend of mine, and I know he loves the camaraderie and being around his teammates. But the game takes a huge toll on the body. Injuries were a factor, but maybe not the biggest one.

While I commend him for doing what he wants and walking away while he is at his peak, I will miss watching him every Sunday. Smith is a great talent who was becoming an NFL superstar. Smith made the Pro Bowl and was coming off the best season of his career.

Smith's departure throws a major wrench in the Vikings' plans. They needed to stockpile defensive players through the draft, but now they may have to make a trade or invest a draft pick to get a running back of his caliber. Daunte Culpepper, Randy Moss, Cris Carter and their offensive line deserve a lot of credit for the Vikings' offensive success, but Smith was the team's MVP last season. Teams had to account for Smith as a fast, explosive running threat, opening up throwing lanes for Culpepper and company. Smith has as much ability as any player to go the distance every time he touched the ball.

Smith's retirement is comparable to Barry Sanders' decision. Sanders was on the verge of being the top rusher in NFL history, but he still walked away and seems to have no desire of returning. For a lot of players, if they can no longer run, tackle or make plays, their self-esteem is shattered. Not for Smith, who is going out on top, off to make a big impact somewhere else in life.

ESPN's Sean Salisbury was Robert Smith's teammate for two seasons in Minnesota.