His success this season could be closely tied to that of Knile Davis.
The Chiefs have given Charles a remarkably light load in training camp and preseason games in an effort to keep him healthy, and that has meant more work for Davis.
But if his backup can be productive enough, the Chiefs may continue to give Charles a lighter load once games start to count, keeping Charles fresher over the 16-game grind than he has been the past couple of years.
''You just want to see that steady No. 2 running back right now that can come in in a pinch or come in and give Jamaal some needed rest, and has that explosiveness,'' Chiefs offensive coordinator Doug Pederson said. ''He's more of your downhill type of runner.''
In other words, he also gives the Chiefs that quintessential ''thunder and lightning'' look, not unlike they had with Charles and Thomas Jones a handful of years ago.
He certainly has proven to be a workhorse.
When Charles was hurt last year against Denver and missed the following week at Miami, Davis ran 32 times for 132 yards and a touchdown. He also had 16 carries for 107 yards while splitting carries with Charles the following week in a drubbing of New England.
But juxtaposed with two performances that set fantasy football afire, Davis also had plenty of forgettable games: 10 carries for 25 yards against San Francisco, 16 carries for 49 yards against St. Louis, nine for 11 yards against Oakland and nine for 23 against San Diego.
Running the ball has never really been an issue for Davis, though. He proved he could do that just fine during a standout career at Arkansas.
The big question has been his hands - his ability to catch the football and hang onto it.
So to alleviate the concerns of Chiefs coach Andy Reid, Davis spent much of his offseason in Houston and Dallas, working out with trainers on his route-running and hands. He wanted to prove that in an offense that demands running backs to catch balls out of the backfield, the bruising running back with a downhill style can be a contributor.
''That's what Andy wants to see me do better,'' Davis said. ''Come out of the backfield and run routes, be in the slot, be out wide, things like that. Be more versatile. I think I've worked on that and I think he can tell the difference, and I think he's gaining confidence.''
No need to wonder whether Reid can tell the difference. Just ask him.
''We knew he was a good runner,'' Reid said earlier this week. ''In the pass game, I think he's improved. He's spent a lot of time working on that.''
He's gotten more time to work on it during the preseason.
Through the first two games, Charles has been on the field for a total of 10 snaps - two in the opener in Arizona and eight last week against Seattle. He has yet to log a carry, touching the ball just three times on short passes.
Meanwhile, Davis has been on the field 51 snaps, including 40 against the Seahawks, when he had 11 carries for 29 yards along with two catches.
Things might change a bit Friday night when the Chiefs play Tennessee, the third preseason game typically being the dress rehearsal for the regular season. Reid said Wednesday that the starters will play three quarters, and that means Charles should finally get some work.
Just how much? That question will be answered in part by his backup.
''I'm feeling confident,'' Davis said, ''and I'm ready for my role to increase.''
NOTES: OLB Dee Ford practiced all week and intends to play Friday night. The Chiefs feared he had fractured his ribs against Seattle, but he wound up having a bruise. ... ILB Josh Mauga worked part of Wednesday's practice with the second team. Rookie Ramik Wilson was with the starters.
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