Posted by ESPN.com's Graham Watson

BYU isn't worried about a short week to prepare for TCU. It's fairly confident it knows what's coming.

High pressure, lots of speed, different looks.

It's a typical Gary Patterson defense. One the Cougars have seen bits and pieces of from both New Mexico and UCLA this year and last. But also one that BYU coach Bronco Mendenhall said is the best he's seen from Patterson during his four seasons at BYU.

"I really like them," Mendenhall said of the TCU defense. "And I'm not only talking in scheme, but fundamentals and effort and coordination in terms of how they work together. You can tell that they trust each other. They know exactly where they're supposed to be and what they're supposed to be doing, and they're very, very confident, as they should be when you look at the statistics that they're putting up.

"Having played against coach Patterson's defenses before, it doesn't surprise me that they're performing like this. And this might be the best group he's had at least since I've been here at BYU."

TCU leads the nation in total defense (207.43 yards per game), rushing defense (20.71 ypg), and sacks (3.86 per game). It also leads the Mountain West in pass efficiency defense (97.94 passing yards per game) and tackles for loss (8.86). TCU is the best total defense the Cougars will face since Wyoming, which is allowing 317.14 yards per game.

The key to TCU's success is in its variations and personnel.

The defensive base is a 4-2-5 where the extra safety is moved around the field to keep offenses off balance. Sometimes that safety will become a linebacker and a linebacker will become an extra pass rusher or run stopper on the defensive line. The Horned Frogs don't script their defense and sometimes a formation can change right before the snap.

That's what can put an offense back on its heels. In one moment, a quarterback could be looking at five secondary players, and in an instant he could be facing an all-out blitz.

What's even more daunting is that TCU rarely substitutes its best players when it's changing formations, so an opponent is always getting the best the Horned Frogs can bring.

"We call it multiplicity, but simplicity," Patterson said. "But BYU, of anybody quarterback-wise, has always seemed to figure it out. Through the years, not just when I've been here, but New Mexico, Utah State, it's been the BYU quarterbacks. Our whole thing is predicated on being good at what we do and trying to give some looks because of the five-man secondary."

TCU studied film of last weekend's game between BYU and New Mexico because the Lobos have been the only team to keep the Cougars' offense in check. New Mexico held BYU to 21 points, the Cougars' lowest score of the season. Prior to that, the Cougars had scored at least four touchdowns in every game. The Lobos held BYU to 45 yards of total offense in the first quarter and 175 yards in the first half.

"They controlled the ball and ran it 50 times and kept [BYU's offense] off the field," Patterson said of New Mexico's effort. "That's as good a defense as I know how to do. The key is you've got to tackle in the running game and make sure you don't let them throw it over your head... They have a way of being able to do that to you with precision passing. You sit on them, then they throw it deep."

But Mendenhall said he's not expecting a lot of deep passes resulting in touchdowns on Thursday. He said the Horned Frogs have incredible "recovery speed" meaning that even if they do get beat, they have enough speed to recover and get back to defend a touchdown.

Although BYU has a grasp on the type of defense it will see on Thursday, there's no denying that it will be the Cougars' toughest test to date. Both teams are undefeated in Mountain West play, and TCU's only loss was to Oklahoma, which moved to No. 1 in the national rankings after the win.

"We've been talking about the BYU game since last January," said Patterson, who noted that there's a blocking dummy in the TCU athletics facility with a BYU helmet on it. "They are the team that has won the conference the last two seasons, so that has to be the mileage marker where you set your sights."