The New York Giants lineup lists Shaun Williams as the starter at free safety and, according to the old-school job description, that should manifest the fourth-year veteran as a guy who plays 10 yards off the line of scrimmage, has great range and "ball skills" and is the defender of last resort for keeping the opposition out of the end zone.

	Brock Marion had 5 interceptions and 96 tackles last season.

But take one look at the 1998 first-round choice, a 6-feet-2, 215-pound specimen who loves to hit and thinks more like a mini-linebacker, and you realize the conventional role of the free safety as traditionally defined by Hall of Fame players like Larry Wilson and Paul Krause doesn't exactly dovetail with Williams' skills.

Then glance at the free safeties around the rest of the league as well -- at defenders like Brock Marion (Miami), Darren Sharper (Green Bay), Brian Dawkins (Philadelphia), and Eric Brown (Denver), among others -- and you comprehend that the standard definition doesn't fit the game anymore, either.

"Nothing against the (free safeties) who used to play 10 or 12 yards off the line, sit back there in a zone, and intercept all those overthrows," said Marion, who is coming off the best year of his career. "But you've got to be more of an all-around player now, one who gets involved in the running game, too. You really have to be a player who combines the skills of a few different positions."

Indeed, the free safety position now dictates that its practitioners be able to "walk down" into the defensive alignment to create an eight-man front against the run, a role that used to be strictly the domain of the strong safety. Free safeties regularly line up man-to-man now against slot receivers and shadow third-down receivers out of the backfield. And it seems the free safety is used more now in blitz packages, too.

Even in the "two-deep" zone alignments that have replaced the "zone-blitz" designs of the '90s as the new scheme of preference, the free safety has to be more than simply a centerfielder who lines up in the middle of the field and shags errant passes. In essence, what defensive coordinators are seeking when they draw up blueprints is a robo-safety, a player who can do a lot of things within the framework of the design.

And increasingly, for safeties, the emphasis is on stopping the run more than defending against the pass. Part of the reason for that is the dearth of so-called "ball athletes," guys with the ability to move naturally to the football when it is in the air, who come into the league every year. Part of it is that, even with the evolution of the game, one thing that remains a constant is the need for a staunch run defense.

So when it comes to the safety positions, the lines have blurred a bit. For some teams, the free safety and strong safety are interchangeable. More defenses are going back to the old style of play, when there was just a left safety and a right safety. And more coordinators are counting on their safeties to perform functions typically associated with linebackers.

	“	Nothing against the (free safeties) who used to play 10 or 12 yards off the line, sit back there in a zone, and intercept all those overthrows. But you've got to be more of an all-around player now, one who gets involved in the running game, too. You really have to be a player who combines the skills of a few different positions. ”
		— Brock Marion, Dolphins free safety

"It's not so black-and-white anymore," said Giants defensive coordinator John Fox. "It used to be that, with the free safety and the strong safety, you wanted two different kinds of guys. But the responsibilities have sort of melded together. It's not unusual now to see the free safety playing down 'in the box' and the strong safety backed off the line. The titles of the positions don't mean as much anymore."

Prime example: Kim Herring started at strong safety for the Baltimore Ravens in 2000, signed with the St. Louis Rams as an unrestricted free agent this spring, and suddenly is a free safety. The St. Louis staff evaluated him, in fact, strictly against the requirements for the free safety position in their new scheme and regarded him as the best fit available.

Despite leading the league in interceptions a year ago, Sharper was used more on the blitz than in the past, and the Green Bay coaching staff has asked strong safety LeRoy Butler to sacrifice some of his aggressiveness to create big-play opportunities for his partner. The ever-active Dawkins rarely plays deeper than a few yards off the line of scrimmage. And Minnesota strong safety Robert Griffith, a tremendous all-around performer who rarely commands the attention he deserves, lines up at free safety and corner in some coverages.

Twenty or 30 years ago, when players like Krause usually led the league with 10 or more interceptions, the free safety position was more rigid. Uniquely skilled defenders such as Ronnie Lott broke the mold, however, and now beauty is in the eye of the beholder and the safety is more in the eye of the storm.

"I like the way the position has (evolved)," said Williams. "You're a part of the action now. Everything is flying all around you. It's become a more aggressive position than it was, I think, years ago. You get a guy with my kind of mindset, that's what you want."

Len Pasquarelli is a senior NFL writer for ESPN.com.