DALLAS — Tom Herman, assessing his Texas squad after the 48-45 win over Oklahoma, inadvertently pinpointed the sore spot which led to Sunday’s ouster of Sooner defensive coordinator Mike Stoops.

“If there’s one compliment a coach loves to get, it is that your guys played really hard, really physical and tough,” Herman said.

Very few football fans have channeled that thought about the Sooners’ defense.

Not against Iowa State last year as the Cyclones turned a 24-10 deficit into a 38-31 victory by scoring on four consecutive possessions amid timid Sooner tackling.

Not against Georgia as OU sprinted to a 31-14 advantage, only to fall 54-48 in overtime in the College Football semifinals at the Rose Bowl.

Not against Army on Sept. 22, despite recording a 28-21 overtime win. The vastly less-skilled Cadets had three scoring drives totaling 235 yards, 51 plays and 28:31 of clock and Stoops’ troops were unable to make one – just one— physical, tempo-altering stop against the option rushing attack.

Oklahoma’s tackling, which has been poor much of the past two seasons, followed suit against the Longhorns.

Texas wideout Lil’J Humphrey recorded nine catches for 133 yards, but it was a third-quarter 19-yarder which drew Herman’s comments to the media.

Humphrey, in a 3rd-and-21 situation from OU’s 46, latched on to a tunnel screen pass well short of the first-down marker but dragged what seemed like a half-dozen defenders at least nine yards. Instead of facing a 4th-and-long decision, Texas converted a 4th-and-2 into a first down, then scored a touchdown five plays later to assume a 31-17 lead and keep the momentum.

“That was the play of the game,” Herman said. “Lil’J is one of the toughest guys we have. That was a culture play.”

Riley didn’t talk about defensive culture. “We missed too many big tackles in the open field. There’s no excuse for that,” he said about OU’s inability to put Humphrey on the ground. “I didn’t think we covered great. We have to be better on the quarterback run-game and third-down plays.”

Texas, entering the game, was averaging 396.6 total offensive yards, seventh-best in the Big 12. The Longhorns, who were held under 400 total yards in consecutive wins over USC, TCU and Kansas State, gouged OU for a season-high 501. Texas had 423 yards in building a 45-24 lead after three quarters.

Oklahoma was ninth in the Big 12 in total defense at 405.2 yards. Only Texas Tech ranked lower. Texas was tied with Kansas at seventh in scoring offense at 28.8 but bullied OU for 48 despite a bit of a vanilla approach down the stretch.

The Sooner defense appeared dazed at multiple points. “Schematically and in other ways, we were just nowhere near good enough for a type of game of this magnitude,” Riley said.

But I point to one statistic which overwhelmingly reflects OU’s lack of defensive efficiency and physicality, particularly in crunch-time situations.

Oklahoma is the worst Big 12 team by far in red-zone defense, surrendering points on all 21 occasions — 17 touchdowns and four field goals. Texas scored touchdowns on four of five red-zone opportunities. Eight of the conference squads hadn’t allowed more than eight red-zone touchdowns entering Saturday’s action.

Oklahoma, on the offensive end, was national championship caliber in 2017. The Sooners have national title-like ammunition this season, but a bad 2017 defensive unit has back-pedaled even more. Save for a tiny ray of fourth quarter sunshine, the defense was atrocious against heretofore an average Horn offense.

Sam Ehlinger is a tough — there’s that Longhorn word again — power-running quarterback, but OU should not have allowed 314 passing yards.

The Sooners, without a go-to pass rusher, were burned several times off three-man rushing schemes.

Ehlinger’s passing yards in the first five games were 263 versus Maryland, 237 against Tulsa, 223 against USC, 255 against TCU and 234 against Kansas State.

Whether or not Oklahoma should have fired Stoops at midseason will be debated in the state and national arenas. But the national perception about OU’s defense was already bad, and it escalated when Texas scored its most points ever against OU.

Stoops, even after being retained, has not been the answer to the problem. As a result, OU is much further behind the eight ball in terms of a college football playoff berth than it was one year ago after falling to Iowa State.

Last year, OU had an ace card, a win over Ohio State. Riley knew if OU ran the table, it carried a huge advantage. There are no supreme cards in the present hand. OU’s sole non-conference victory over a Power-5 foe came against UCLA, currently 0-5.

There were large numbers of OU fans and former players who begged for Stoops’ dismissal during the 2017 regular season and after the Rose Bowl collapse.

OU’s administration didn’t oblige but must wonder in retrospect if a firing then wouldn’t have been easier for some observers to stomach.

There are scant few who will argue a change isn't absolutely necessary. OU’s stagnant defense has become an albatross to a dynamic offense which is deserving of at least the opportunity to earn national championship status.