Lubbock, Texas ? Texas Tech coach Mike Leach knew something had to change when the Red Raiders rolled up 718 yards last year against Oklahoma State — and lost.

The offensive wizard’s days of merely tolerating defense were over. It turned out that all he had to do to fix things was walk a few doors down the hall to the office of a coach who came with him to Lubbock seven years earlier.

Ruffin McNeill’s promotion to defensive coordinator after that deflating 49-45 defeat transformed the Texas Tech defense perhaps more than Leach could have imagined. The No. 2 Red Raiders won’t be confused with the defensive stalwarts of the Southeastern Conference, but they don’t have to be when they pass for 400-plus yards and score at least 40 points nearly every week.

Across-the-board improvement by the defense under McNeill played a major role in positioning Texas Tech (10-0) for a run at the national championship, the next step coming Saturday night at No. 5 Oklahoma (9-1).

McNeill’s plan wasn’t complicated. In fact, it was simple — as in simplifying schemes, defensive lineman Jake Ratliff said.

“He wanted us to quit thinking and go play football,” Ratliff said. “That’s the way it should be: when in doubt, just go attack. There’s no thinking involved.”

Ratliff praised McNeill’s predecessor, Lyle Setencich, whose hiring five years ago led to a similar uptick in Tech’s defensive performance. The Red Raiders held pretty steady on defense under the man who gave Leach his first college coaching job 20 years ago.

But there was something different about that day in Stillwater, Okla. Perhaps it was Oklahoma State having three 100-yard rushers in a game for the first time ever — and gaining 366 yards on the ground — that led Leach to question the toughness of the Tech defenders.

A day later, Setencich stepped down for personal reasons, and Leach made Ruffin the interim defensive coordinator.

In their final nine games, the Red Raiders went from ninth to first in total defense in the Big 12 (405.5 yards to 347.6); 10th to fourth in scoring defense (28.2 points to 24.9); seventh to first in pass defense (206.8 yards to 180.2); and 11th to eighth in rush defense (198.8 yards to 167.3 yards).

“The biggest thing is Ruffin’s passion about football,” Leach said. “I think he makes the rest of the staff passionate about football as well as the players. They are all out there excited to play, which I think is really key.”

The defensive numbers aren’t much different from those in several seasons under Setencich. But the record is. The two biggest games of the season — back-to-back wins over then-No. 1 Texas and Oklahoma State that put Texas Tech front and center in the national title chase — each had a different stamp from the defense.

Against the Longhorns, Tech scored the game’s first points on a safety and dominated defensively most of the first half.