Two positions in transition

Mamas, don't let your babies grow up to be fullbacks.

While fullbacks will always be part of pro football, the state of the position is tenuous. Vonta Leach's release by the Baltimore Ravens last week concluded an offseason in which fullback salaries have been sacrificed for other positions.

Leach was scheduled to make $3 million in the final year of his three-year deal with the Ravens. He's a three-time Pro Bowler and one of the best fullbacks in the game. As great as he was in Houston, the Texans couldn't afford to keep him after a Pro Bowl season in 2010 and let him go.

Longtime Jaguars fullback Greg Jones made $3.5 million last year, but the Jags didn't try to re-sign him. He ended up signing a one-year, $1 million contract with the rival Texans.

The trend toward more spread offenses in college has made it tougher and tougher to find pure fullbacks. It's forced NFL teams to convert players from other positions to open holes for a halfback.

The rapid evolution of the tight end has made it even tougher to keep fullbacks around. Teams are finding it easier to pay a versatile tight end and let him do the blocking and pass-catching from an H-back position.

The Eagles, for example, had no problem giving James Casey $4 million a year to move from Houston, where he was a tight end, H-back and fullback. To be able to make any money as a fullback, a player has to do more than just block.

Want a scary stat? The average salary for a starting fullback is scheduled to be $1.1 million in 2013. That's $750,000 less than the average salary for kickers and $512,000 less than the average salary for punters. The average salary for a fullback is what top veteran long-snappers receive.

Salaries are so scaled back that only six fullbacks are making more than $2 million a year. Le'Ron McClain of the San Diego Chargers is the highest-paid fullback at $2.75 million a year. John Kuhn of the Green Bay Packers, Jerome Felton of the Minnesota Vikings, Mike Tolbert of the Carolina Panthers and Michael Robinson of the Seattle Seahawks each earn $2.5 million a year.

Robinson, though, has to battle sixth-round pick Spencer Ware to keep his job. Fortunately, he has more to offer than just being a fullback. He is great on special teams and is a leader in the locker room.

Marcel Reece will make $2.023 million from the Oakland Raiders this year. He has longevity because he can double as a halfback and can catch at least 50 passes a season.

While the fullback position contracts, the tight end position continues to expand. Offensive coordinators have been spreading the wealth to tight ends, and those pass-catchers are seeing their bank accounts grow.

In many offenses, tight ends are becoming slot receivers. The great ones, in fact, are starting to be paid like wide receivers. The process started when the Patriots rewarded Aaron Hernandez and Rob Gronkowski a combined $16.5 million a year.

The agent for Packers tight end Jermichael Finley threatened to challenge the Packers if they gave him the franchise tag because of the number of times he lined up in the slot or was flexed out at wide receiver. Jared Cook did the same thing with the Tennessee Titans. By avoiding the tag, Cook got a five-year, $35.1 million deal with the St. Louis Rams.

Watch for New Orleans Saints tight end Jimmy Graham to follow that strategy after the season when he becomes a free agent. He'll be angling for a $9 million-a-year deal similar to Gronkowski's.

Teams have found the value of using two tight ends, and some incorporate three-tight end packages. Some tight ends are so good they can pass off as wide receivers. The 49ers, for example, are thinking about using Vernon Davis at wide receiver while Michael Crabtree is recovering from his torn Achilles. That would allow Anquan Boldin, who is listed as a flanker, to move to his normal spot in the slot.

Football is an ever-changing sport. That's great for tight ends and bad for fullbacks.