a 55-17 whipping on his Texas Longhorns. Well, to be fair, that was just one of the low points.
The next one came a year later, same place, same Sooners, essentially the same result: Oklahoma 63, Texas 21. "The last two years, it was over before it started," Brown said.
That wasn't the end of the low points, though. There was another this year, so that makes three seasons in a row and a reasonable explanation why Mack Brown, 16 years, 153 victories and one national championship into his tenure at Texas, is fighting for his coaching survival as old Oklahoma comes sweeping down the plains looking for a fight this Saturday.
[Forde-Yard Dash: College football still acting backwards in a progressive society]
"The Brigham Young game," Brown said of the latest of the lows, referring to the Cougars' 40-21 annihilation of the 'Horns on Sept. 7. It was a game of utter futility that seemed to stun a coach who had gone into the season preaching the potential of his rebuilt club. BYU rushed for a whopping 550 yards, prompting Brown to fire his defensive coordinator, Manny Diaz.
"It was awful," Brown said. "It was awful and embarrassing. And you just can't do it. The rest of it, we've been in games, we've competed. But you can't do what we did at Brigham Young, you can't do what we've done the last two years against OU."
After the BYU loss, Brown sat on the charter flight home from Provo and watched the game footage, seeing a lack of effort and execution that, well, nearly caused the need for an airsickness bag.
"It made me want to throw up, it made me sick," he said. "I absolutely despise the way we looked at Brigham Young. It's not what we are supposed to be doing.
"It's not who Texas is."
Who Texas actually is, of course, is the question.
There may not be a more publicly pleasant man in college football than Mack Brown. He's 62, polite and folksy, still very much the product of Cookeville, Tenn., a small city a little over an hour east of Nashville.
On Monday he ran through his media duties – multiple press conferences to the state's vast media contingent (one for electronic, one for print), some from town radio shows, another from the omnipresent Longhorn Network. He did it with the same smiling, welcoming, even joking, manner as ever.
If it wasn't widely assumed, you wouldn't know he was fighting for his coaching life. Texas is 3-2 and even some of the wins have been criticized. His longtime boss, athletic director DeLoss Dodds, has announced his retirement. His other longtime boss, school president Bill Powers, is battling with a slew of regents himself, according to an OrangeBloods.com report.
Plenty of fans are apoplectic about the state of the program and eager to express that on social media and talk radio. Former players, including no less than Earl Campbell, have said it's time for the coach to go. Brown's eventual demise is such a forgone conclusion the media has basically moved on to speculating on who will replace him.
Amidst all of this, Mack Brown is still here, trying to put on a brave face and find a way to beat the Sooners. Get that done and he might still need to run the table to keep his job. It's all or nothing as the pressure mounts.
"Ten years ago I couldn't have handled it," Brown told Yahoo Sports on Monday, sitting in the press box overlooking massive Darrell K. Royal Stadium, which was expanded to over 100,000 capacity, in part, because of the success of Brown's recent teams.
"This place matures you, it hardens you," he continued. "So I've blocked it out and I'm doing what I'm paid to do. I'm coaching as hard as I can, and I'm trying to be honest and direct and understand everyone has a job to do and everybody has their opinions.
"I may not always agree with them, but I also haven't done what I need to be doing. We shouldn't have two losses. I understand that."
His players, far more wired into social media than their coach, bristle most at the popular suggestion that Brown doesn't care anymore, that he isn't in there fighting alongside them.
"He's a great man," said quarterback Case McCoy.
Brown is appreciative but philosophical. The pitchfork brigade is about the bottom line and he's 25-18 since the start of the 2010 season.
"The only way to fix any misperception is to win. I know that. What you say has nothing to do with perception." He says he still has plenty of support. The negative comments by fans and former players make headlines, but not the texts and emails of support from other guys he coached, not the warm wishes of good luck he gets when out to lunch.
He kind of shrugs it all off. It's a whole new ballgame from when he started as an assistant coach in the early 1970s, or even his first head coaching spot at Appalachian State in 1983. He's paid more, of course, and he knows that. It's all part of the deal.
He isn't looking for sympathy.
"This is a wonderful place and our fans have been great to us," Brown said. "The fact people say what they want to say, that's OK. It's something coaches are going to have to deal with for the rest of their careers. Twitter and Facebook, it's different now. Everybody has a voice. Everybody has a platform and everybody is a reporter. That's OK. That's what it is.
"We won a national championship here , played for another  and got close on another [2004, 2008]. That's all in the past. It's about today. That's just the way it is. Fair or not, who cares?
"I don't get to vote on what's fair."
Brown is 6-9 against Oklahoma in the annual game held in Dallas, right smack dab in the middle of the Texas State Fair. Some of those losses have been beyond lopsided. Still, he treasures the event, a showcase for the program and a challenge for everyone. It's why you want to coach at UT. It's why you want to play at UT.
His first exposure to it was in 1984, when he was an Oklahoma assistant. The Sooners team bus pulled through the fair grounds to the Cotton Bowl and fans began rocking it to intimidate them. Then OU coach Barry Switzer turned to Brown, saw the look on his face and laughed.
"Now you're getting it," Switzer said. "Now you're getting how big the game is."
Brown's 16th Red River Showdown as Texas' head coach is his biggest yet because it may very well be his final one. The 'Horns have shown little promise this year. No. 12 Oklahoma may be a bit better than anyone expected.
Las Vegas has the Sooners as a two-touchdown favorite, a massive spread for this game. A blowout would be ugly. There's a bye week following, and who knows what happens if there is another low point.
"I don't look at point spreads," Brown said.
It's probably for the best.
This is when Mack Brown loses the kindhearted grandfather/gentleman persona. He's a Hall of Fame coach, a national championship coach, a coach with 239 career wins and scores of players in the NFL, not to mention a lifetime of great memories and better relationships.
He has nothing to prove. Yet suddenly, back to the wall, he has everything to prove.
"I do," he said. "I do. Not just this weekend, the rest of the year. I'm still trying to win the conference championship after we got off track there. That's the competitive nature. You don't coach for 30 years as a head coach without being a competitor.
"I don't like it. I don't like losing. I don't like it for Texas. I don't like it for our fans. I don't like it for DeLoss and Bill. I hate that they have to take up for me. That's not my style at all. I don't like it but I understand it.
"I just need to do the work to make sure we get this fixed."
Win on Saturday, spring the upset, rustle up the Longhorns of old, enjoy that sweet moment when half the stadium, the maroon-clad half, shuffles out as all the burnt-orange fans gather and serenade them with a victorious rendition of the "Eyes of Texas," and well, who knows what's possible?
New life for Mack Brown. Perhaps.
"We need to win, simple as that."
After all those years and all those games, amid an onslaught of darts and doubts, Mack Brown is bowing up and trying to delay it all, trying to silence the critics and stave off the successors, trying to prove, once again, that he isn't just some nice guy, some politician as coach.
If this is it, if this is the end, he only promises to go out his way, head held high, fists clinched and swinging.
"I'm a proud man," Brown said. "I'm still fighting."
That much is undeniable.