ORCHARD PARK, N.Y. -- The Buffalo Bills' trip Sunday to a soggy, freezing Arrowhead Stadium in Kansas City was going well through the first half, when Sammy Watkins caught six passes for 158 yards and two touchdowns.

Then, as Watkins was targeted just once in the second half and held without a catch, the Bills collapsed, allowing the Kansas City Chiefs to come from behind for a 30-22 victory.

Part of the problem, Watkins said after the game, was that the Bills lacked a killer instinct and a "sense of urgency" after halftime.

"I was basically talking about really the whole team," he explained Wednesday. "Body language. They go and score, we got to line back up and make plays and go out there, I think. We get down in the game, guys that [are] not getting balls get down and when I don't get the ball, I get down.

"So it's really staying consistent throughout all the plays. Blocking throughout the whole game. I think I kind of died down a little bit in the second half. I got to stay alive and stay playing fast and competing."

So was it a mental hurdle for the team?

"Not really the mental thing," he responded. "The weather, the clouds -- it's little things like that you can't let affect your game. You can't fall asleep when they're holding the ball for six minutes. Things like that, you got to stay in tune.

"You can't worry about what the defense [is] doing. You got to really control what the offense can control, and the defense gives up a touchdown, we got to go out and score a touchdown. If the defense stops the offense, we got to go and score. It's vice versa. We got to compliment each other."

Watkins believes the Bills would have "won most of their games" if they played the way they did in the first half against the Chiefs. The key, he believes, is keeping a positive attitude.

"I don't need nobody telling me, 'Man, we got scored on.' Stuff like that brings you down," he said Wednesday. "You can't listen to that. We got to really stay together as a whole team, which I think we do, for the most part. Third and fourth quarter, we just slipped a little bit and we just need to refocus sometimes. Come out in the second half and get on the [other] team and put the nail in the coffin, basically."