The chorus of boos echoing throughout Arrowhead Stadium in the fourth quarter proved the first hint. And the second hint occurred when seats began to empty following quarterback Alex Smith's interception with 9:56 remaining in the game.
Still, the fans weren't alone in feeling upset about Sunday's 23-7 loss to the Indianapolis Colts (10-5), as players also voiced their displeasure of the game during the postgame locker room session.
"They came in today and kicked our ass and we deserved everything we got," cornerback Dunta Robinson told reporters. "No excuses. You have to look in the mirror and we have to decide what kind of team we want to be moving forward.
"OK, you dominate Oakland, yeah, you dominate the Redskins, but what are you going to do when we face other powerhouses? We're a much better team than what we showed today and we have to play like it."
Wide receiver A.J. Jenkins echoed Robinson.
"It definitely puts things in perspective," Jenkins said. "When you're winning, you hear how good you are. Since we took the L, people got to look in the mirror; we have to man up and see what's going on. That's what we're going to do."
Meanwhile, the Chiefs (11-4) are bound for the playoffs and locked in as the No. 5 seed.
But observers wouldn't know that given Week 16's performance, which was arguably the worst the season.
Offensively, the Chiefs started fast, scoring on the first possession with running back Jamaal Charles' 31-yard touchdown run.
The rest of the game proved a disaster.
The Chiefs committed four turnovers - quarterback Alex Smith accounted for three (two interceptions, one lost fumble) - were penalized seven times for 65 yards, went 1-of-8 (13 percent) on third down and gained just 22 yards of offense in the third quarter.
"It's hard to win with that many turnovers against a good team," tight end Anthony Fasano said. "We have to go back and scrutinize the film technically what went wrong, but glaring, it's just the turnovers and not taking advantage of opportunities. Three-and-outs are not the way to win football games."
How the Chiefs lost Sunday hasn't been seen in Kansas City since a former regime. But this year's Chiefs aren't the dysfunctional team of a season or two ago. And that's a good thing, as evidenced by the words of linebacker Derrick Johnson, one of the team leaders.
Johnson gave credit to Colts before giving a passionate response, a message of accountability, to a group of reporters when asked what happened Sunday.
"First off, hats off to them," Johnson said. "They came in, had a game plan and they executed. They beat us. No excuses. If we're going to go all the way, which we plan to, we can't ever play like this. There is no excuse; we have to get better."
The players' reactions to Sunday's loss are in line with what coach Andy Reid told reporters when asked how to avoid discouragement.
"I would expect our players to be upset over this and that's what I sensed in that locker room," Reid said during his postgame media session. "A lot of time and effort went into preparing, same thing with the coaches and if you're not, then there's something wrong with you."
In the meantime, what will assist the players in not getting down is knowing they can lean on each other with the playoffs looming on the horizon. Kicker Ryan Succop said camaraderie will ensure the team fights through it.
"You look around the locker room, obviously all our coaches, and we got a lot of guys who are going to be mentally tough and definitely stick together," Succop said. "We'll learn from it and we'll build from it, then we'll go from there."
Where the Chiefs go in the postseason is a likely rematch against the Colts in the first round.
And if the Chiefs learn from Sunday, Johnson's prediction of a different outcome could come true.
"We'll see them again," Johnson said of the Colts. "They got the upper hand on us right now because in their minds, they think they can beat us. If we go down there (to Indianapolis), it will be a different story."