OXFORD, Miss. (AP) -- Mississippi coach Hugh Freeze did much of his homework on Texas before the season even began.
Now he's left wondering if all that study time will have any use.
In a flip of the script that few saw coming, it's No. 25 Ole Miss (2-0) that will be the nationally ranked program on Saturday in Austin, Texas.
The Longhorns (1-1), on the other hand, are sorting through the aftermath of a disastrous loss to BYU that resulted in coach Mack Brown firing defensive coordinator Manny Diaz and replacing him with Greg Robinson.
Changing coordinators after the second game of the season is certainly not an ideal situation for Texas. But it's also shaken Freeze, who doesn't know how much Robinson's defense will change the Longhorns.
"There's probably no way that I can answer that until we get there," Freeze said. "I've never experienced this before. It is an unknown. Whether or not it's a great challenge, I don't know."
The Ole Miss offense certainly seems like it would give Texas trouble. The Rebels are effective running the ball -- especially using the read-option between quarterback Bo Wallace and running back Jeff Scott -- and that's exactly what the Longhorns couldn't stop while allowing BYU to rush for a whopping 550 yards.
Wallace said he hopes the Rebels can take advantage of the matchup.
"That's what we do," Wallace said. "But I know that all week they're going to be trying to fix that. We have to execute. But as long as we execute, I think that no matter who we're going to play we're going to be able to get some yards."
Freeze said he doesn't expect Robinson to make drastic changes to the Longhorns' scheme or personnel, but sometimes even small details are enough to throw an offense off balance.
"I usually go into a game and have a good idea of what you're going to get on third down," Freeze said. "This one, not so much. I don't think it can be a wholesale system change, but I do think he can spend some time getting his stuff ready for those situations."
The BYU loss certainly takes some of the aura away Texas heading into matchup, but Wallace scoffed at the notion that the Rebels might let their guard down.
He said the team has been looking forward to the game for a long time and hopes to show how much it's improved since last year's meeting, when the Longhorns walloped the Rebels 66-31 in Oxford.
"They beat us by 30 points last year," Wallace said. "They have better talent than us or more depth at least."
The Ole Miss defense was particularly embarrassed by last year's performance. Linebacker Serderius Bryant said the Rebels are out to prove they're faster, stronger and can handle the Longhorns' offense.
Bryant led the Rebels with 15 tackles against Southeast Missouri on Saturday. He compared the intensity of the preparation for this game to the Egg Bowl, which is the Rebels' annual meeting with Mississippi State.
"To tell you the truth, this is like our (Mississippi State) this year," Bryant said. "The way (Texas) came on the field and put it on us last year, we feel like we've got to get revenge. We've got to have a chip on our shoulder."
Texas safety Adrian Phillips said the Longhorns expect to see a very motivated opponent this weekend.
"Of course we beat Ole Miss pretty bad last year, so they're going to come out here and try to do the same thing to us," Phillips said. "With the performance we had last week, they're going to feel like we're vulnerable but we can't be. We're going to have to get after it."
Texas quarterback David Ash remains questionable for this game after suffering head and shoulder injuries against BYU.
Ash has been held out of practice and Brown said Wednesday he's still waiting to hear from team doctors on Ash's status for the next game. Brown says a final decision could be delayed until Saturday.
Ash accounted for five touchdowns for the Longhorns in a season-opening win over New Mexico State. He had two touchdown passes against BYU.
If Ash can't play, the Longhorns will start senior Case McCoy with freshman Tyrone Swoopes as the top backup. McCoy has six career starts.
Top 25 Overview
It's difficult to say who needs this win more: Texas, on the verge of imploding after canning its defensive coordinator or newly ranked Ole Miss, which just cracked the top 25 for the first time since 2009. Longhorn drama aside, winning is still a tall order for the Rebels.