B OULDER, Colo. — The thing about it was, nobody knew why. Nobody, apparently, could fully process such calamity.

The Sooners weren’t tough enough?

Nobody dared say.

They weren’t ready to play?

Maybe, but nobody was talking.

For the first time all season, Oklahoma was hit in the mouth. And once hit, well, everybody saw what happened in the second half.

It’s an old football cliché, but maybe it works. Not that any Sooner on his way out of the visiting locker room had put it together.

Juaquin Iglesias came closest, but all he said was this:

“We looked like a totally different team,” he said. “That didn’t look like us … No, that didn’t look like us.”

He might have said it again. Kind of like becoming trapped in an internal monologue, only out loud.

Why not?

For everything OU had done against North Texas and Miami and Utah State and Tulsa, Saturday afternoon at venerable yet charming Folsom Field was, for the Sooners, the antithesis of all that had come before.

Sam Bradford had been great. Against the Buffs, he was OK at best.

The receivers had been great. Against the Buffs, they dropped as many as they caught.

The offensive line had been magnificent. Against the Buffs, they sprung Allen Patrick for 56 first half yards on 10 carries, but not much else.

The defensive line just got pushed around.

How does that happen?

“They just really outplayed us,” Bob Stoops said.

“We just didn’t make plays,” began Lewis Baker. “And when you have the opportunity to make plays, you have to make plays, and we didn’t do that today.”

“There were some competitive plays we needed to make and we didn’t it,” said Kevin Wilson, whose juggernaut offense picked up 230 yards or, put another way, 438 fewer than it gained against North Texas, 181 fewer than it gained against Miami, 387 fewer than it gained against Utah State and 323 fewer than it gained against Tulsa.

Just so we’re straight, the Sooners didn’t make plays.

But that can’t be the story. Not the whole story.

Not for Colorado, which made the plays and deserved to win if only because the most dangerous guy on the field was quarterback Cody Hawkins, the Buffs’ redshirt freshman who outdueled Bradford on a day both of them played the best defense they’ve yet faced. And not for the Sooners either, because it just sounds like some sort of cop out.

Remember, the thing Stoops likes most about this team is the way it goes about its business. When he explains it, he knocks the nearest wood. “Robotic,” he calls it, but in the best possible way. That should help at the Cotton Bowl in six days, but how could it let the Sooners down so suddenly with nothing less than the season on the line because the season’s on the line every week in the college game.

At least until you lose.

OU had committed six turnovers through four games. They committed three against the Buffs alone.

Colorado had the ball almost 39 minutes. The Sooners had it barely 21.

“For whatever reason,” Wilson said. “We couldn’t handle success.”

Maybe it’s because these Sooners are still so young.

Maybe it even had something to do with the altitude.

“That took a toll,” Patrick admitted.

And still, OU led 24-7 and appeared on the edge of putting it away.

Then came an interception, a killer off Iglesias’ hands, and a couple fourth-down conversions from the Buffs, whose most dependable play seemed to be third (or fourth)-and-everything-breaks-down.

“We couldn’t get off the field there,” defensive coordinator Brent Venables said, repeating himself like Iglesias. “We couldn’t get off the field.”

That’s the way it went.

OU couldn’t make plays and when the defense finally got a stop, here came a turnover.

Finally it all came down to a 45-yard field goal from Kevin Eberhart, 4 yards longer than he’d ever kicked one that counted, and from behind it looked like he hooked it only it straightened out and soon the fans were swarming the field.

That’s what happened. Maybe even how it happened.

The mystery was why it happened.

Like it was somebody else out there.

Nobody seemed to know.