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	After eight great seasons, the San Diego Chargers need to begin contemplating life without LaDainian Tomlinson.

Posted by ESPN.com's Bill Williamson

It is time for the San Diego Chargers to find a replacement for LaDainian Tomlinson.

It is not, however, time to replace the star running back.

But that's the whole idea. The Chargers have to be prepared for when Tomlinson can't be their bell-cow back. Get ready, Chargers fans, that time is coming. It is only natural to think Tomlinson is nearing the end of the line. That's not a knock on the future Hall of Famer. It's just part of life for NFL running backs.

LaDainian Tomlinson #21 RB San Diego Chargers 2008 STATS ATT YDS TD AVG LNG 292 1,110 11 3.8 45

Tomlinson will be 30 in June. This season, he had the fewest rushing yards of an eight-year NFL career, and he's starting to get banged up. He battled a turf-toe injury in the first half of the season and then had a groin injury that kept him out of the last six quarters of the Chargers' season. San Diego's 35-24 loss in the AFC divisional playoffs was the first game Tomlinson missed because of injury in his career. Tomlinson could be facing offseason groin surgery.

Yes, Tomlinson is showing signs of slowing down. After the loss in Pittsburgh, Tomlinson said his goal was to stay healthy in 2009.

"I'm going to be 30," Tomlinson said. "I want to be able to play every game."

It has gotten to the point in his career where Tomlinson's NFL mortality is suddenly in question. On a San Diego radio station earlier in the week, Tomlinson said he has heard trade rumors but he didn't know the team or teams supposedly involved. The Chargers shouldn't trade Tomlinson. He still has value to the team and, as the ace of the franchise, should be in San Diego until he can no longer be an effective NFL player.

But it's time for the Chargers to start thinking ahead. Tomlinson has shown enough wear and tear that they should start thinking about how to spell him before it becomes an urgent issue. San Diego can't be caught unprepared in 2010 and be forced to try to find a replacement.

The 2009 draft is a perfect time to start looking. San Diego has the No. 16 pick. The Chargers have other needs, with most on the defensive side of the ball. They could use another linebacker or safety or even a defensive lineman or an offensive lineman. But there are no super pressing needs.

If San Diego falls in love with a running back, this could be the time to take him.

Running backs Chris "Beanie" Wells of Ohio State and Knowshon Moreno of Georgia both could be standouts in the running game. Both could be available when San Diego picks. The Chargers have to consider this option.

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	Darren Sproles is an ideal role player for the Chargers, but may not have the size to be an every-down back.

If the Chargers do end up taking Wells or Moreno, it doesn't need to mean the end of Tomlinson in San Diego. But because of his contract, age and recent injury history, it is not out of the question that Tomlinson will not be with the team in 2010, so a rookie could be groomed while spelling Tomlinson this season.

If this team is going to have Super Bowl aspirations in 2009, having an extra running back won't hurt the cause. The team's other needs could be addressed in free agency. Getting Tomlinson's replacement in free agency probably wouldn't work because tailbacks have such short shelf lives. If you are going to get a legitimate runner, the draft is usually the way to go.

Some may think the Chargers don't need to get a new running back because they have Darren Sproles. Sproles is a free agent. The Chargers need to re-sign him, but not to be Tomlinson's eventual replacement. Sproles is a terrific backup and change-of-pace back. Sproles is also one of the best return men in the league and is valuable as a receiver.

But Sproles is too small to be a 300- or 400-carries-a-season back. He was terrific as Tomlinson's replacement against Indianapolis in the wild-card round. But Sproles, 5-foot-6 and 181 pounds, struggled on the ground against Pittsburgh as the lead back. He is best suited as a role player. The Chargers need a bigger lead back.

Tomlinson is not going to be there forever. San Diego needs to start looking for his replacement before it is too late.