Former Dallas Cowboys running back Marion Barber ended his career Friday when he announced his retirement from the NFL at age 28.

It was classic Barber: No news conference, just a statement through his team -- the Chicago Bears.

For a few years, Barber was a force with the Cowboys, who gave him a seven-year, $45 million contract in 2008. At the time, it was deemed the right move because the franchise was moving on from Julius Jones.

Then, Barber started to break down.

His bruising style began to catch up to him. He never lost his starting job but it was clear that he wasn't the same despite leading the team in rushing for three consecutive seasons (2007-09).

Routine 5-yard runs turned into 2-yard runs. He didn't have the same explosviness as in years past. Thigh, toe and knee issues cost him games and his ability to run people over.

His teammates loved his style and that he gave up so much of his body.

But after six seasons and 4,358 rushing yards, sixth-most in franchise history, it was just time for the Cowboys to move on. Felix Jones took over this season and now he's been replaced by DeMarco Murray as the starting running back.

For as much as people want to replace Tony Romo around here (I find the talk silly), looking for Emmitt Smith's replacement seems harder to do more than anything else.

There is a long list of starters the Cowboys have employed to replace the all-time rushing leader, and it will grow again in 2012. Barber was supposed to be one of those players, but it didn't end that way.