By Len Pasquarelli
ESPN.com

INDIANAPOLIS -- The NFL's change of emphasis on the defensive line, equal parts revolution and evolution, continued here this weekend.

For the second year in a row at the annual NFL predraft combine workouts, the defensive tackle pool was far deeper than the defensive end class, and the inside position figures to be well represented again in the first round next month.

There were six defensive tackles chosen in the opening stanza of the 2001 draft, the most ever, and this year's lottery could rival that record. Five of the first 19 choices in 2001 were tackles and that early interest in the position could be reprised.

"We never used to see this kind of quality and quantity (at defensive tackle) in the past," said Cleveland Browns defensive coordinator Foge Fazio, whose team selected tackle Gerard Warren as the third overall player in the '01 draft. "It has traditionally been one of the toughest positions to fill. But recently, at least, there's more than just one or two needles in the haystack."

Bill Parcells and the late George Young of the New York Giants concocted what they defined as the "Planet Theory" years ago. In its simplest terms, it postulates this: there is a limited number of people on this planet who weigh 300 pounds and are in shape; if you have a chance to draft one, you'd better.

This weekend, it seemed, most of the people who comprise the subspecies in the "Planet Theory" were here for the combine and playing defensive tackle. It was an impressive bunch physically and, even if many of the top prospects didn't participate in all the drills, personnel directors and general managers were excited by second straight bumper crop of tackles.

"Guys this big aren't supposed to be this athletic," said St. Louis assistant coach Bill Kollar, arguably the NFL's premier defensive line mentor. "But this is where the game is going. You can't just put a big slug in there anymore, someone who can't move and just takes up space, and expect to win that way. It's getting to be a premium position."

Even with another seven weeks of evaluation before the April 20 NFL Draft, draft boards around the league are already reflecting that, and teams that didn't fill their tackle needs a year ago will get another shot at it.

And a few of this year's tackles could become truly dominant players in the league.

The University of Tennessee alone has two -- John Henderson and Albert Haynesworth -- who will go off the board by the middle of the first round. Ryan Sims, who played in the shadow of sackman end Julius Peppers at North Carolina, and Wendell Bryant of Wisconsin, are certain first-rounders. Other tackles with first-round potential include Anthony Weaver of Notre Dame, Washington's Larry Tripplett and Fresno State's Alan Harper.

Besides the fact the well-spoken Tripplett had his name misspelled on the back of his combine-issue sweatshirt -- "Tropplett" it read, a source of obvious irritation to the Washington standout -- the defensive tackle prospects garnered much respect.

Defensive tackle has gone from a grunt position to a glamour category. It's indicative of how the game has changed at all levels just in the past four or five years. It used to be that every team wanted the "edge" pass rusher -- the explosive, upfield defensive end who could create havoc from the outside.

Teams will pay for an outside rushman -- Exhibit A is Leonard Little, who got a $17.5 million deal and a $5 million signing bonus fromt he Rams on Sunday -- but more than ever before, the action now begins with the tackles, and the game is played from the inside out.

"One thing is that, at every level, offensive coordinators seem to run to run the ball more," said Henderson, who after a superb 2000 season played much of the 2001 campaign with a high ankle sprain that severely limited his productivity. "So you still need a big body in there who can stuff the run. Rushing the passer is still kind of your second job, but more guys can do it now, and it seems like tackles are better trained to compress the pocket."

The preponderance of West Coast-style offenses in the league certainly has contributed to the new emphasis on the defensive tackle position. In the West Coast passing attack, virtually every ball is thrown from a three- or five-step drop, and quarterbacks are tutored to make a quick read and unload. That means the defensive ends, forced to loop to the outside, typically arrive at the quarterback a split second after he has released the ball.

The tackles, though, have a more direct avenue to the quarterback. And more tackles are now being permitted to play one-gap techniques, meaning they can penetrate quicker. There aren't as many "stunts" being run by defensive coordinators anymore and so the priority is to locate tackles capable of simply beating blockers right off the snap.

"The shortest distance to any point is still a straight line," said Tripplett. "That's why so many teams now expect their tackles to contribute to the pass rush. Personally, I still like stuffing the runner right back into the hole, but it's fun to get a sack every so often, too."

The odds are pretty good he's going to get the chance.

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