One can only imagine his shock during that second stanza, and both overtime periods, when his crew could not make a meaningful, significant play against an offense they had dominated in the first half, holding the Gamecocks to just 70 yards and 3 offensive points.
"We executed poorly and didn't make any plays when the opportunities were there," said Nix postgame, looking as if the blood had drained from his face. "Jacksonville State created turnovers. We didn't.
"The ball hit us in the hands a couple of times in the open field and we didn't take advantage of those situations. We expect to make those plays."
Indeed. That's what veteran defenses, defenses expected to carry the bulk of the load in the early going of the season, do.
"We prepared for a multiple offense and knew they had two quarterbacks they would use. We were aware of what they were going to do," Nix continued. "The only difference in the second half and the first half was that they ran the sprint out pass a few times. I saw flashes of good things, particularly early, but as a coach, you really only remember the mistakes when you lose a close game.
"The bottom line is that we played good football for three quarters. We didn't make the plays at all in the fourth quarter and that is not what we expected. Coming into this game, we felt like our front seven was one of the strengths of the team. It takes 11 and we didn't get it done. We took a loss and the defense didn't help our team win."
Despite the fourth quarter lapses that kept JSU in the game and enabled them to eventually tie it up and send it into overtime, one play sticks out as the decider, the coup de gras.
Facing 4th and 15 at the 30 in the second overtime, JSU QB Coty Blanchard scrambled and found Kevyn Cooper in the back of the end zone - by inches - for the score that eventually led to the game-winning two-point conversion.
"We called a three-deep zone and in that case you always stay as deep as the deepest receiver, no matter what. For whatever reason, our young man came up for a split second and let the receiver get behind him. We just didn't do our job there," Tyrone stated.
The two-point conversion that won the game for JSU also stuck in Nix's craw.
"It looked like we had it stopped, but their QB improvised, dumped it off and we couldn't get the receiver on the ground. Game of inches. . . .We had the right call there," his voice trailed off.
Nix would not allow talk of DE Kentrell Lockett being out fall in the excuse category.
"We missed him, for sure. He's one of our leaders and captains, but that's no excuse. We felt the young me we had out there were ready to play and knew what they were facing," said Nix.
Where does the Rebel defense go from here? Certainly, the shock has to wear off quickly. Practice Sunday.
"We have to evaluate our character and determine how badly we really want it," he closed. "If they are the men I think they are, they will come out and respond. We'll go to work tonight evaluating ourselves and we'll expect to go out the next game and perform at a high level from the beginning until the end of the game.
"We will learn how to finish. Next time we'll respond in a positive fashion."
Co-Offensive Coordinator Dave Rader was as simple and shell-shocked as Nix was in his explanation of the contest.
"I don't know what to tell you other than the old football adage - turn the football over and you lose," said Rader. "It's really that simple.
"We had three turnovers, two of which killed drives we felt we had going."
The Rebel offense hit the same wall the defense did, so it seemed.
After a strong start where it looked as if everything was clicking and it appeared a romp was on with 31 first-half points, the Reb offense was held to a mere 3 points in the second half of regulation.
"We got some big plays early and got some points. We jumped up 14-0 real quickly and everything looked smooth," noted Rader. "Then the big fumble by Nathan (Stanley) gave them a cheap score.
"Even after that, we came back and scored two more touchdowns."
Then, that was it. As quickly as the Reb offense had turned on to start the game, the faucet turned off in the second half.
Ole Miss used two quarterbacks - Stanley and Jeremiah Masoli (Randall Mackey has agreed to a redshirt year). Both, for the most part, got an OK from Rader.
"Nathan started off really well. Then Jeremiah came in and did some good things in the first half and then in overtime, where we felt the threat of the option and use of the option game would be needed," Rader stated.
Two drives in the second half were stopped by turnovers. One, a Jesse Grandy fumble and the second a Masoli-thrown pick.
"We stress ball security and forcing things constantly and for us to treat the ball so loosely today is certainly disappointing," he noted. "Like I said, it's simple. If you don't hold on to the ball, you lose the game.
"Our continuity was pretty good and we were moving the ball well except for the turnovers. Those things just killed us from finishing this game out."
The Rebels rolled up 479 yards of total offense, but the Achilles heel of the day, from an offensive standpoint, was the three critical turnovers.
Obviously, it's regroup time for the Rebels, on both sides of the ball.
Certainly not the way anyone in a blue jersey planned the lid-lifter for the 2010 season.