Depending upon one's point of view the fullback spot in the NFL is either one at which nearly half of the teams in the league have spent free agency attempting to consciously upgrade, or, more accurately in most situations, a position where the moving parts are simply interchangeable.

No matter the perspective, though, this much is clear: It is a position that is experiencing unparalleled turnover this offseason.

For players who don't touch the ball very often, fullbacks certainly are on the move, and at least 13 teams figure to have new starters in 2003.

Gash returns to Bills

Unrestricted free agent fullback Sam Gash, who made the Pro Bowl squad in each of two years during a previous stint with the Buffalo Bills, on Monday evening returned to the club after playing the last three years with Baltimore. The 34-year-old Gash, an 11-year veteran, has long been regarded as one of the premier lead-blockers in the league. He will replace Larry Centers, released by the Bills last week, as the starter. Centers holds the league record for most receptions by a running back, but became less a factor in the Buffalo offense last year, as coordinator Kevin Gilbride relied more on a three-wide receiver formation. Gash should be a tremendous escort for emerging Buffalo tailback Travis Henry, who rushed for 1,438 yards in 2002. While he is not as effective a receiver as Centers, it likely won't matter much if Gilbride keeps the same design he used last season. A selfless player whose bone-jarring blocks have cleared the way for backs from the New England Patriots (1992-97), Bills (1998-99) and the Ravens (2000-2002), Gash has just 120 rushing attempts of his own. --Len Pasquarelli, ESPN.com

"It really is a position," said Philadelphia head coach Andy Reid, "where you almost have to check every day to see who has gone where. There has been an (inordinate) amount of movement."

Consider just this one dizzying domino-like sequence: Pro Bowl fullback Lorenzo Neal of Cincinnati signed with San Diego, where he replaced the jettisoned lead-blocker Fred McCrary, who then moved to New England to take the starting spot once held by Marc Edwards, who went to Jacksonville as a free agent to man a position that didn't even exist for the Jaguars in '02.

The Oakland Raiders lost Jon Ritchie to Philadelphia in free agency, and to take his pace signed Cecil Martin, who played the first four seasons of his career with, you guessed it, the Eagles. The Buffalo Bills last week released Larry Centers, the all-time league leader in receptions by a back, and he is now being pursued by Washington which, let's see, cut him two years ago.

For whatever reason, fullback has become the "musical chairs" position for this spring's free-agency period, a status typically afforded the quarterback spot in past years. And in some cases, it seems, there are teams that haven't been especially particular about who they have sitting in the fullback seat when the music stops playing.

As long as they've got someone with experience, that is, at performing in a role which has now become one of the NFL's most thankless professions.

One veteran fullback suggested last week that fullback might well be the most inappropriate named position in the game. His rationale: It might be labeled fullback, but the position is decidedly part-time for most of its practitioners.

"They may throw you a bone once in a while with the rare (rushing attempt), but the position really has evolved into one where you're a blocker and you catch the occasional pass," said Detroit Lions fullback Cory Schlesinger. "I mean, the satisfaction you get from being a battering ram all day and from basically putting yourself in a human demolition derby mode, has to come from feeling good about opening a hole for somebody else."

	Neal

Certainly the fullback spot has de-evolved into one of vicarious pleasures and vicious collisions. Most fullbacks spend the game going head-to-head with linebackers, trying to knock defenders out of the hole or, if they are fortunate enough to even be on the field for third down, picking up the blitz in pass protection.

Not surprisingly, of the seven fullbacks to whom ESPN.com recently spoke, five claimed to have had at least one concussion in 2002. Bob Christian, the former Falcons starter who was forced into retirement last month when two specialists suggested it was too risky for him to ever play again, suffered a pair of concussions last season.

The unheralded Christian was characteristic of the modern-day fullback, who has gone beyond even throwback terms, in terms of an active role as a ball carrier. Former quarterbacks assistant Jack Burns last year referred to Christian as "the glue" of the Atlanta offense.

But until the offense becomes unglued without him in the lineup, few fans will truly appreciate how significant a role player he was in the past several seasons. That's because, like most fullbacks in the league now, he labored in relative anonymity.

	“	I mean, the satisfaction you get from being a battering ram all day and from basically putting yourself in a human demolition derby mode, has to come from feeling good about opening a hole for somebody else.”
		—Cory Schlesinger, Lions fullback

"We're just kind of extra blockers, but we wear lower (uniform) numbers, that's all," said Neal, whose nine carries in 2002 were only four fewer than he had totaled over the previous four seasons. "(Bengals tailback) Corey Dillon might know if I'm doing my job but most fans have no idea because the fullback doesn't touch the ball anymore."

There were 27 teams in 2002 who listed a starting fullback on their depth charts, the balance being two-tight end clubs, or teams whose base offense deployed in a three-wideout set. The starting fullbacks for those 27 teams averaged just 15.8 carries for the season.

Absent the 146 rushes logged by Mike Alstott of Tampa Bay, who really is an "ace" formation tailback but keeps getting miscast as a fullback when it comes time to vote for the Pro Bowl squad, the 2002 average plummets to a measly 10.8 carries for starting fullbacks. That means the average fullback in the NFL in 2002 carried the ball once every game and a half.

Arguably the two best pure fullbacks in the league, Tony Richardson of Kansas City and San Francisco's Fred Beasley, totaled just 48 rushes for the season and combined for just 88 "touches." There were 16 starting fullbacks in 2002 who had fewer than 10 rushing attempts each and seven of them had either no rushes or just a single carry.

Little wonder that Neal, whose signing bonus in San Diego was $1 million, is the lone fullback this spring to change teams and collect a seven-figure upfront payment. Three others -- James Hodgins of Arizona ($900,000), Edwards ($875,000) and Dallas' Richie Anderson ($800,000) -- received signing bonus of more than $750,000 but the fullback position still ranks near the bottom of the salary chart.

And based on the wholesale movement of the past month, with franchises switching their starting fullbacks like they change socks and turning them into near-faceless placeholders, the postion nears the bottom of the priority list for many teams in the league.

Len Pasquarelli is a senior writer for ESPN.com.