INDIANAPOLIS -- You would think he was an undrafted rookie free agent coming from a Division III school if you closed your eyes and just listened to words coming out of his mouth.

"I don't let another man judge me because another man couldn't do it."

"I let them say he's this or that. I keep that in my head when I'm training and try to prove them wrong."

That's not one of the many undrafted rookie free agents trying to catch the eye of a team during minicamp. It's Indianapolis Colts running back Frank Gore.

Yes, that Gore, a veteran running back who is preparing for his 13th NFL season and within striking distance of becoming the fifth all-time leading rusher in league history.

Frank Gore hopes to run over Father Time and keep moving up the all-time NFL rushing list. Robert Deutsch-USA TODAY Sports

Gore is currently eighth in NFL history with 13,065 rushing yards. He can make a substantial leap ahead of Eric Dickerson (13,259), Jerome Bettis (13,662) and LaDainian Tomlinson (13,684) to move into fifth on that last list by rushing for 620 yards this season, something he's done in 11 of his 12 seasons. Gore would have to rush for 1,037 yards to pass Curtis Martin for fourth all-time.

"I hear it," Gore said. "Edge [Edgerrin James], Fred T [Taylor] tell me to keep going. They think I can get top 4 if I just keep being me and keep training. As long as I'm healthy and feeling good and I'm on the field and get the opportunities, that will come."

Each yard Gore, who has only missed 12 games in his career, pounds away on the ground will further help him make his case for the Hall of Fame. Tomlinson's enshrinement this summer will mean that every retired running back ranked in the top 10 in rushing will be in the Hall of Fame.

"I would never bet against Frank Gore," Colts offensive coordinator Rob Chudzinski said. "He's a special, special guy and for him to do what he did last season is incredible. I've got all the facts and the stats and everything else how rare that is. He's a Hall of Famer. That's the bottom line. There's something special there. You never bet against those kind of guys."

Gore, cornerback Darius Butler, defensive lineman Kendall Langford, defensive lineman Al Woods and the ageless wonder Adam Vinatieri -- who is 44 years old -- are the only players over the age of 30 still with the Colts as new general manager Chris Ballard commits to a youth movement.

Gore turns 34 years old on May 14 and knows people question how much longer he can be successful.

He became the first running back in 32 years to rush for at least 1,000 yards while being at least 33 years old (John Riggins was the last to do it pre-Gore, rushing for 1,239 yards in 1984). Gore also became the first Colts running back since 2007 to rush for at least 1,000 yards in a season.

"I don't listen to what people say outside," Gore said. "I don't let another man judge me because another man couldn't do it. I still love the game and I'm training and I'm still having fun. Just because this guy didn't do it doesn’t mean I'm not going to do it. I keep that on my shoulders. I'm a shoulder guy. I'm going to show them and I'm not listening to what they've got to say."

Gore, who is headed into the final year of his contract, doesn't have a timetable on how much longer he plans to play. He's taking it year-by-year and evaluates himself on how he competes against younger players in the offseason.

The reality -- and numbers -- say the running back position is meant for younger players. Gore, as confident as they come, isn't buying that notion. His 1,025 yards last season were good enough for 12th in the league.

"They try to make it that, but when you look at all the backs, they try to praise after one year, the next year they fall off," he said. "I've been playing 12 years, easy I could have been top five if I had more opportunities, but it ain't about that. When you look at the numbers, I'm still in the mix with all the young guys they try to praise. I let them say, 'He's this or that.' I just keep that in my head when I'm training and try to prove them wrong."

That's why it won't be surprising one bit if Gore is sitting in fifth place on the NFL's all-time rushing list at some point in the 2017 season.