LaDainian Tomlinson admitted "it was time to move on" after announcing his retirement as a San Diego charger after a stellar 11-year career in the NFL.

"I knew at the end of the season last year that it (retirement) may be a possibility," Tomlinson said during a news conference.

"It probably took some time. I had the better part of five months to contemplate what I wanted to do. You weigh the pros and the cons and I realise there was more for me off the field than there was on the field and that's how I looked at it.

"It wasn't because I did not want to play anymore. That wasn't the reason. It was simply time to move on."

Tomlinson said he understood what another Chargers legend Junior Seau, who passed away on May 2, said about retirement. "One thing I remember is when Junior Seau, when he retired and he was up here, standing up, giving his speech. One thing that stood out to me is he said 'I'm graduating today.' And that's the way I look at it.

"I've been playing football twenty-something years, and so at some point, it almost seems like school every year. Where you sacrifice so much, and there's so much that you put on the line -- mentally and physically, with your body, everything.

"And so today, I take the words of Junior Seau. I feel like I'm graduating. I really do, because I've got my life ahead of me.

"I'm healthy, I'm happy with a great family, and I'm excited to now be a fan and watch you guys play."

Tomlinson felt his 11-year career went by in a blur. "It went so fast. I feel like I came into the league just yesterday," the 32-year-old told the NFL Network. I remember the draft clearly, my first mini-camp, my first game, and now I'm retiring all of a sudden after 11 years.

"It has definitely gone by fast, but at the same time I have enjoyed every single moment of it."

Asked if there was a chance he would change his mind about retirement, Tomlinson said: "I'm a 100 percent retired."