KANSAS CITY — The Chiefs need a proven running back to take some of the load off Jamaal Charles. LaDainian Tomlinson will soon need a new job.

If Tomlinson can accept a secondary role, at least initially, this union makes too much sense for it not to happen.

First, look at this from the Chiefs perspective. Charles’ emergence the second half of last season was the best thing to happen to the Chiefs offense since Dick Vermeil and Al Saunders walked out the door.

Charles looks like a legitimate threat, someone the Chiefs can build around.

But let’s not put him in the Hall of Fame just yet. Let’s not forget that until halfway through last season, Charles was a fumble-prone third-down back.

A lot of backs can produce for short periods of time. The great ones do it for longer periods and we’re still unsure whether Charles can handle that kind of pressure over a full season.

It’s certainly worth finding out whether he’s capable of thriving like that, but the Chiefs need a backup plan in case he buckles.

Even if Charles becomes the player of Kansas City’s dreams, he’s going to need some help. At 200 pounds, Charles isn’t capable of 20-plus touches for 16 games.

Right now, the Chiefs backup candidates are barely worth mentioning. I like Kolby Smith as much as anyone. More importantly, the Chiefs are intrigued by his abilities. But his last two seasons have been ended prematurely by injuries.

The Chiefs can’t count on him again until he proves he can stay healthy.

They could always draft a back but they have bigger priorities in the early rounds. Then they’re taking a chance on a guy drafted in the middle or late rounds.

The Chiefs know what they’re getting with Tomlinson. Sure, he’s near the end of his career. But the Chiefs aren’t asking him to be what he was for so many years with San Diego.

Unless Charles fails or is injured, Tomlinson is a 15- or 20-play-a-game guy for the Chiefs and still capable of producing on a smaller scale.

It’s more problematic whether Tomlinson would accept such an arrangement once he’s released by the Chargers. If he wants to be the starter, then forget I even mentioned this. But if he’s willing to accept the realities that face a 30-plus running back with a lot of wear and tear on him, then this is the place for him.

He’s not going to win a Super Bowl in Kansas City in whatever time he has left but he will have a part-time role that could develop into something bigger. That might be the best he can hope for.

The Chiefs should be willing to oblige.