KANSAS CITY — Three years after the Kansas City Chiefs drafted Derrick Johnson as a playmaking linebacker, they’ve finally decided to let him be one.

Told to forget about the details and techniques of his position and fly to the ball as he had done as an All-American at Texas, Johnson responded with perhaps his finest game as a pro. He had seven tackles and half a sack, made an interception and forced a fumble that led to a touchdown in Kansas City’s 33-19 victory over Denver last Sunday.

On Wednesday, he learned he had been named AFC defensive player of the week.

“He was always trying to read everything exactly right,” said coach Herm Edwards. “You still have to read your keys, but he’s athletic enough to where if he just sees the ball, he can make a lot of plays. I think he started seeing the ball better, not worrying so much about techniques. The technique’s going to come.”

The breakthrough game by the 6-foot-3, 242-pounder could not have come at a better time. The Chiefs (1-3) had lost 12 straight games going back to last Oct. 21.

“I knew it was a big game, a division game,” said Johnson. “I wasn’t thinking a lot. I didn’t really care if I messed up. It wasn’t that I wasn’t going to play within the scheme. It’s just that I was putting it all on the line.”

Johnson, drafted out of Texas in the first round in 2005, was projected from the outset as a star. But his career has been slower to take off than most people expected — a product, Edwards said, of his being subjected to different coaches and different schemes while trying to adjust to the NFL.

Key to his change in approach was a meeting with defensive coordinator Gunther Cunningham.

“Back in Texas, I was more of a freelance player within the defense,” Johnson said. “Let me shoot gaps; let me do my thing. One thing Gun kept telling me was, 'Just put all the scheme out of your mind, all the responsibilities out of your mind. You know the defense entirely. Just go out there and play like you’re at Texas.’”

And so he did. He came out of nowhere to make a leaping, athletic interception of Jay Cutler’s pass in the third quarter. In the first half, in one of the game’s key plays, he saw the ball wasn’t in his area so he struck out on his own and mined gold. His hit on star wide receiver Brandon Marshall caused him to cough up the ball.

Cornerback Brandon Flowers scooped it up and ran it back to the 2, setting up Larry Johnson’s go-ahead TD in one of the most-needed victories any Kansas City player or coach ever experienced.

“I anticipated. When you anticipate something going on you can react really fast,” Johnson said.

“After he took a couple of steps, I was already in the backfield. That second effort, ripping the ball out, I actually didn’t know it was out. I went for it. That’s what we do in practice all the time, ripping it out. I’m on top of him and I see Brandon Flowers and everybody trying to chase him.”

It’s not as though Johnson hasn’t tried to use his speed and quickness since coming into the NFL.

“Don’t get me wrong. I’m not saying it’s night and day from how I’ve been playing,” Johnson said. “But you can move so much quicker when you don’t have to think about what you have to do. Gun’s allowed me to go there.”

The fourth-year linebacker said the full effect of the victory, and his part in it, didn’t hit him until he got home.

“I started exhaling when I went home,” he said. “When you’re out there on the field you’re trying to make plays. You’re expecting to make plays. I was more excited with the win. But at the same time, you want to play well. I definitely had a pretty good game. I want to repeat that, man. That felt really good.”