Kansas City, Mo. ? After losing for the first time this season, some of the Kansas City Chiefs may be having difficulty concentrating on this week’s game, even though it’s against archrival Oakland.

“Honestly, I’d be happier if it was Cincinnati again,” cornerback Eric Warfield said following Wednesday’s practice. “But we can’t do that.”

It was Warfield who got beat on Peter Warrick’s 77-yard touchdown catch in the fourth quarter of the 24-19 loss to the Bengals Sunday, a loss that ended the Chiefs’ perfect season and dropped them to 9-1.

But he was not the only culprit.

“A lot of missed tackles. A lot of missed tackles,” defensive tackle Ryan Sims said with a sigh.

Still bugging the Chiefs is the fact Cincinnati wide receiver Chad Johnson had “guaranteed” the Bengals, then 4-5, would beat the NFL’s last unbeaten team.

“It was very disappointing to get a loss the way we did, to have somebody talk noise before the game started, and suffer that loss,” said Warfield, who’s been having the best season of his six-year career. “But that’s a done deal. That’s behind us. We need to take the mistakes we made in that game and move on from there.”

Even Sims, who was singled out for praise by coach Dick Vermeil after the game, seemed to be thinking back to the Bengals Wednesday.

“We’ve got to be renewed,” Sims said. “Let it be a wakeup call. Everybody’s been waiting for us to lose, and we lost. So now we can just get on with it.”