Offense at Oklahoma was going to change.

That’s why the Sooners of 1999 came out slinging the football through the air.

That’s why so many passing records at OU immediately became history. That’s why the wishbone and all its subsequent incarnations o5cially died that chilly December back in 1998.

Mike Leach running Hal Mumme’s spread offense had worked wonders in the Southeastern Conference and made a contender out of doormat Kentucky. There was no reason why it couldn’t turn the run-oriented Big 12 upside down.

“I was very emphatic with even the other (coaches) that we hired that we weren’t going to have a conglomeration of ideas and put that on the field,” Stoops said last week, offering an insight into this week’s opponent, Leach’s Texas Tech Red Raiders. “I said, ‘This is what we’re doing.

We’re committed to it.

We’re doing it totally this way, what Hal, Mike and those guys did at Kentucky, and we’re going to be good at it. And then if we evolve from there as the years go, so be it. But we’ve got to evolve from somewhere. This is how we’re going to begin.’ ” That first recruiting class produced a trio of accomplished quarterbacks. Josh Heupel set the standard and won a national title. Nate Hybl won a league title and a Rose Bowl. Jason White won the Big 12 and the Heisman.

Then came league titles from Paul Thompson and Sam Bradford and a whole bunch of blue-chip QBs.

Maybe more. Now, with Stoops in his 10th season in Norman and Leach in his ninth in Lubbock, Texas, the Big 12 is a different league.

OU and Tech are different programs, different offenses.

Saturday’s game between the No. 5 Sooners and No. 2 Red Raiders — the winner could get all the Big 12 and Bowl Championship Series marbles — is the culmination of a decade of foresight by Stoops and Leach.

“Ten years later,” Stoops said, “we’ve evolved into whatever we have now.”