CHARLOTTE, N.C. (AP) -- Panthers fullback Mike Tolbert is used to defenders underestimating him when he has the ball in his hands.
He's hoping they continue to overlook him.
The squatty 5-foot-9, 245-pound Tolbert doesn't look like he'd be tough to tackle or is particularly fast.
Tolbert's low center of gravity and surprising speed has made him a valuable and versatile commodity for the Panthers (9-3), who beat Tampa Bay 27-6 on Sunday for their eighth straight victory.
''They see a guy that is short and fat and they think, 'Oh yeah, we got him no problem.''' Tolbert said with a laugh. ''Then they are like 'Whoa, where did he get those feet from? I didn't know he was that fast.'''
Tolbert's physique has been the source of some good-natured ribbing from teammates, who like to pick on him just as much as he likes teasing them.
''In the locker room he has a lot of nicknames,'' quarterback Cam Newton said.
Newton said he calls Tolbert ''tub of goo'' and said backup quarterback Derek Anderson pegged him as ''Patty Mayonnaise. Tub of Mayonnaise.''
The QB said others call him ''Sugar Bear.''
''If y'all don't get my gist, he's a big mass guy,'' Newton said. ''He may not look good running, but he gets the job done. ... He's a player you would hope that he's on your team. He brings a lot of energy to the huddle, brings a lot of energy to this team.''
And football smarts, too.
Panthers coach Ron Rivera, who played nine seasons in the NFL and has coached 17, said Tolbert is ''about as smart of a football player as I've been around.''
That's one of the reasons why Rivera pushed former general manager Marty Hurney to sign Tolbert as a free agent in 2012. Rivera had worked with Tolbert in San Diego.
''He understands the offensive concepts, what to look for in terms of blocking and protections,'' Rivera said. ''He understands running the ball and using blocks and setting up blocks. He understands how to run a route, how to beat man coverage and beat zone coverage. ... He has a natural feel for the game and is able to pick things up really well.''
Offensive coordinator Mike Shula said Tolbert's football IQ and versatility mesh perfect with Carolina's offense.
He said Tolbert's ability to play halfback, fullback and tight end - as well as special teams - make him tough to keep off the field.
''He has built in leverage, which I think is important in this sport, and really good balance, too,'' Shula said. ''... He plays with an attitude of toughness and whatever it takes. We feel lucky to have him.''
Tolbert was used primarily in short-yardage and goal-line situations last year in Carolina and most of his four seasons in San Diego. His 30 touchdowns rushing since 2010 are tied for sixth-most in the NFL.
But on Sunday with DeAngelo Williams out with an injury and Jonathan Stewart struggling to pick up yards, the Panthers turned to Tolbert more often between the 20s and in longer down-and-distance situations.
Tolbert didn't disappoint, racking up 89 yards from scrimmage.
Rivera, a former linebacker, smiled when asked how he'd tackle Tolbert.
''I don't know,'' Rivera said. ''I know that he'd hit me in the chest, that's for sure.''
Tolbert, 28, is far from fancy.
After Sunday's win, he pulled on a dark hooded sweatshirt with two pit bulls plastered on the front. He said he owns two pit bulls. In the locker room he's the resident comedian and teammates say you can often hear his voice from across the room.
But on the field, he's all about producing.
Tolbert has quietly run for 301 yards and four touchdowns and caught 19 passes for 145 yards and two TDs.
That may surprise some. But it certainly doesn't surprise Tolbert, who has turned a college career at tiny Coastal Carolina into a successful six-year NFL career.
''Everybody underestimates me - for a minute,'' Tolbert said.
NOTES: Rivera said he expects Williams, defensive Charles Johnson, linebacker Chase Blackburn and tight end Ben Hartsock to return to practice Wednesday.
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