As the saying goes, there's a thin line between love and hate. In sports, there's an even thinner line between retiring while on top of your game, and playing well past the point your talents have eluded you. For professional athletes nearing the end of their careers, it's hard to figure out which side of that line they fall on. Even the all-time greats don't get it right.

Jimmy Smith retired on Thursday. An unassuming man playing in the small media market of Jacksonville, Florida, most people wouldn't recognize Jimmy Smith if he passed them in a Piggly Wiggly. Yet he was the face of the Jaguars' franchise ever since their inception. He was that guy you always wanted on your fantasy team because of his consistency year after year. With the exception of 2003, Smith was good for a solid 70-80 catches, 1200 yards and 6-7 touchdowns every season since 1996. Those numbers tell the story of a decade of excellence for the 5-time Pro Bowler. Yet Mr. Smith will probably fall short in his bid for election to Canton's hallowed Hall. That's what happens when you play in an era with contemporaries by the names of Moss, Harrison, Owens, Brown, Carter, et al. Even still, Jimmy Smith should - and will - be commended for his numerous achievements on the football field. He should be commended as well for the fact that he walked away while still at the top of his game. That's not the easiest thing for a player to do.

Brett Favre was awful last year. Brutal. Always known as a player who would sometimes force a bad pass into a bad spot, he threw 29 of said passes last season as his Packers endured a character-testing 4-12 season.

Let the record show that the blame for Packers' disappointing performance should not lie entirely on the right arm of the Gunslinger. He handed the ball off to such luminaries as Samkon Gado and Noah Herron. Threw it to studs by the names of Andrae Thurman and Taco Wallace. Still, it was clearly evident that there was something missing on the fastball of #4.

As such, we've had to endure the "Will Brett Retire?" saga throughout the entire off-season - Favre and the Packers going back and forth like two bickering lovers who can't get enough of each other. The Gunslinger eventually decided to give it one more shot, despite the fact that the Packers' front office hasn't really improved the team, as Favre had demanded sometime around Act IV of the drama. In reality, it wasn't about getting better pieces around him at all. It was about whether or not Favre believed that he still had "it" in him.

It's completely understandable that those who were once at the pinnacle of their respective sports find it hard to come to grips with the fact that they no longer can do it anymore. Brett Favre has played football his entire life. Ever since he was a youngster growing up in Kiln, Mississippi, he was driven to succeed at the highest level. 396 touchdowns, one Super Bowl trophy and a first-class ticket to the Hall of Fame is proof positive that he did just that. So for someone who is used to being one of the best at what he does, how do you know when it's time to walk away?

Every time Michael Jordan donned the unfamiliar blue-and-white jersey of the Washington Wizards, he firmly believed that he had one more great game, one more spectacular move, one more picture-pefect jumper in him. And sometimes, he was absolutely right. But on most nights, the old Mike - the MJ that we all had hung, taped, and thumbtacked to our bedroom walls as a child - was nowhere to be found.

There's no clock that tells you that your time is up, no advisor whispering in your ear that it might be in your best interests to seek an alternate line of employment. So sometimes, against the wishes of friends and fans alike, you decide to strap it up for one last shot. And maybe, just maybe... you'll be able to recapture that old magic.