SPARTANBURG, S.C. (AP) Ron Rivera can't imagine the Carolina Panthers without fullback like Mike Tolbert on the roster.
The 5-foot-9, 250-pound Tolbert does a little of everything for the NFC champions - blocks, catches passes, carries the ball and even contributes on special teams. So it's hard for Rivera to fathom how nearly one-third of the league didn't even carry a fullback on their rosters last season.
''I couldn't tell you why teams don't,'' Rivera said. ''I think that is one of the missing links in the league to be able to have an effective running game, to have lead blockers and guys who can get dirty down inside.''
It has worked for Rivera and the Panthers.
The Panthers have run for at least 100 yards in an NFL-best 32 straight games, including the playoffs. They were second in the league in rushing last season and first in scoring and reached the Super Bowl before losing 24-10 to the Denver Broncos.
That success is why the Panthers didn't hesitate to re-sign the 30-year-old Tolbert to a two-year, $3.3 million contract after he became an unrestricted free agent. All things considered the Panthers might have gotten a bargain for a guy who has been an All-Pro two of the last three seasons.
Then again, it's not as though fullbacks are the Pokemon Go of the NFL.
The Miami Dolphins are among the teams that don't employ a true fullback.
Dolphins coach Adam Gase said after careful consideration the team decided they couldn't afford the luxury of having a ''specialty position'' like fullback on the roster.
''Where we kind of ran into the problem was that we liked staying on the ball, we didn't like changing personnel and we always liked the fact of having a guy that could play the fullback role (but) still be a guy that we could flex out plus play in-line,'' Gase said. ''We're really being a little pickier as far as we want a guy that can do it all, and then play special teams as well.
''We didn't want to get stuck in a spot where we had some experience with a fullback when we were first at Denver and he was getting like eight plays a game. We just felt like let's get the guy out there that is going to play 30 plays a game on just offense, plus special teams.''
The Jacksonville Jaguars stopped carrying a fullback prior to the 2015 season after they hired offensive coordinator Greg Olson to replace Jedd Fisch.
Olson's offense simply doesn't use one, relying on backs to find holes and using more multiple tight end sets up front.
''We don't use one in any of our offensive sets so no sense in carrying one if we're not going to use one,'' Jaguars general manager Dave Caldwell said.
Some teams are reincorporating the fullback into the offense.
The Philadelphia Eagles have gone back to using a traditional style running game following the departure of coach Chip Kelly. They've moved tight end Trey Burton to fullback.
But the importance of the position has been undeniably downgraded.
''A lot of the game nowadays is predicated around the quarterback,'' said Tolbert. ''You try to develop him first as a passer, where as in the old days it was more about the run game and defense. It's not that way anymore.''
Tolbert collected 256 yards rushing and 154 yards receiving last season for the Panthers and scored four touchdowns.
He also played on most of the special teams.
Tolbert said the key to surviving is changing with the tide and remaining versatile, knowing well that the days of true smash-mouth fullbacks like Lorenzo Neal, Daryl Johnston and Tom Rathman may be over for good.
''You have to do special teams and pass protect and block out of the backfield and run routes,'' Tolbert said. ''You have to be able to do different things than in the past, more than just being a bang-your-head-against-the-wall fullback.''
AP Sports writers Mark Long in Jacksonville, Florida, Steven Wine in Miami and Rob Maaddi in Philadelphia contributed to this report.
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