Aside from nerves that make butterflies in the stomach feel like they've grown to the size of pterodactyls, there is one thing shared by nearly all of the area's high school football teams still alive in the playoffs: Four of the five run a variation of the spread offense.

Baylor, Boyd-Buchanan, Calhoun and South Pittsburg all switched from more traditional offenses to the spread in the last three years, while Ridgeland continues to cling to the wing-T that has brought coach Mark Mariakis so much success.

The four spread teams hope the quick-strike potential of that offense carries them through tonight's round of playoff games.

Born out of the run-and-shoot, the spread typically features one back and as many as four receivers spreading the defense thin across the field, creating space for the skill-position players. The offense also has introduced more athletic quarterbacks as run-pass dual-threat options.

While Calhoun uses the offense as a pass-first attack -- highlighted by quarterback Taylor Lamb's 2,600-plus aerial yards this season -- Baylor, Boyd-Buchanan and South Pittsburg use it to create more space in the running lanes for a variety of ball carriers. They still run a lot of the same plays they would from the old-school wing-T or "I" formations, but by using the shotgun spread they manage to send two defenders out of the box and into space, allowing their speedy running backs more room either to shake free or outrun would-be tacklers.

Each of those three teams has a 1,000-yard rusher this season.

"I still believe that no matter what formation you line up in, you cause the most headaches and win the most games by being able to run the ball and be fundamentally sound on defense," said Boyd-Buchanan coach Grant Reynolds, whose team has outscored opponents an average of 31-9 going into tonight's quarterfinals. "I know most people now want to see the high-scoring offense because it's exciting, but one drawback of the spread is that a lot of teams have gotten away from practicing defensive fundamentals.

"It's tough to tackle good athletes in space, but it's even tougher if you don't spend time working on it. We see a lot of teams that just try to outscore you. They're hoping to get a turnover or that you'll make a mistake so they can get the ball back and score as quick as they can. They're not really concerned with playing defense.

"That might work for a while, but eventually you run into somebody who is pretty sound, so you had better be too."

Over the last 10 years the high school game has seen a dramatic shift of emphasis placed on quick-strike offenses. From the proliferation of summer 7-on-7 passing camps and the infusion of more finesse athletes -- mostly from the basketball courts who had shied away from football because it was too physical -- the spread has gone from niche offense to the preferred formation for most area teams.

Of 50 area programs surveyed, 39 run some form of the spread now. And there is a dramatic difference in points scored this season, compared to 20 and even 10 years ago.

Twenty years ago Cleveland and Marion County were the Chattanooga area's two highest-scoring teams, averaging just more than 32 points per game. The Blue Raiders ran the wing-T and Marion's Warriors were still duping opponents better than anyone else with their split-back veer.

Ten years ago Tyner was the area's highest-scoring team at 38 per game, but no other area team averaged more than 31.

This season, with more teams preferring to replace big, physical linemen and fullbacks with quicker, more athletic bodies, 20 area teams averaged more than 32 points per game and four averaged 42-plus, led by Signal Mountain's 48.3-per-game average. Ten area teams averaged more than 300 yards of offense per game.

The average combined points scored in a game involving area teams has gone from 37 in 1991 to 41 a decade ago to 58 this year.

Also in 1991, there were three 1,000-yard rushers in the area, one 1,000-yard passer and only one receiver who had more than 430 yards. The number of 1,000-yard rushers was double that in 2001, and the number of quarterbacks with more than 1,000 passing yards increased to six.

This season there are 21 running backs with more than 1,000 rushing yards and five more who had at least 900. There are also 20 quarterbacks with 1,000 passing yards and six who surpassed 2,000 yards. Eight receivers had more than 800 yards.

"You can score so much quicker now getting the ball to the best athletes out in space instead of just lining up in an I-formation and trying to cram it down the field," Baylor coach Phil Massey said. "It's about getting mismatches now instead of just lining up and seeing who is the most physical.

"We've got different type athletes playing the game now. It's not just the biggest, most physical kids; it's the little quick, speedy guys who can turn it up the field and make a big play at any time. It's exciting but it's awfully tough to stop. To be honest, it's a nightmare for defensive coaches."