Aside from those who are already trained in combat sports like wrestling and other martial arts, it seems like a safe bet that a number of NFL players could find success if they crossed over to MMA. They push their bodies to withstand the physical toll of an entire season through repeated impacts, lifting weights and cardiovascular conditioning. Strip them of their pads and helmets, and they are still true gladiators in terms of physicality and mental toughness.

Herschel Walker remains perhaps the best known former NFL player to make the jump. He was a three-time NCAA All-American at the University of Georgia, where he led the Bulldogs to a national championship in 1980 and won a Heisman Trophy in 1982. Walker went on to play 12 seasons in the NFL with the Cowboys, Vikings, Eagles and Giants. A longtime martial arts practitioner, he fought twice under the Strikeforce banner despite debuting at the age of 47: He stopped Greg Nagy with punches in January 2010 and did the same to Scott Carson a year later.

Here are some of the NFL players who have traded in their facemasks for four-ounce gloves:

Herschel Walker

MMA Record: 2-0
NFL Team(s): Dallas Cowboys, Minnesota Vikings, Philadelphia Eagles, New York Giants
College(s): University of Georgia

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Matt Mitrione

MMA Record: 13-5
NFL Team(s): New York Giants, San Francisco 49ers, Minnesota Vikings
College(s): Purdue University

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Brendan Schaub

MMA Record: 10-5
NFL Team(s): Buffalo Bills
College(s): Whittier College, University of Colorado

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Eryk Anders

MMA Record: 10-1
NFL Team(s): Cleveland Browns
College(s): University of Alabama

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Wes Shivers

MMA Record: 7-1
NFL Team(s): Tennessee Titans, Atlanta Falcons
College(s): Mississippi State University

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Rex Richards

MMA Record: 7-2
NFL Team(s): Indianapolis Colts
College(s): Texas Tech University

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Brock Lesnar

MMA Record: 5-3
NFL Team(s): Minnesota Vikings
College(s): University of Minnesota

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Marcus Jones

MMA Record: 4-2
NFL Team(s): Tampa Bay Buccaneers, Buffalo Bills
College(s): University of North Carolina

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Greg Hardy

MMA Record: 3-0 (Amateur)
NFL Team(s): Carolina Panthers, Dallas Cowboys
College(s): University of Mississippi

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Austen Lane

MMA Record: 2-0
NFL Team(s): Jacksonville Jaguars, Kansan City Chiefs, Detroit Lions, Chicago Bears
College(s): Murray State University

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Alonzo Spellman

MMA Record: 1-0
NFL Team(s): Chicago Bears, Dallas Cowboys, Detroit Lions
College(s): Ohio State University

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Michael Westbrook

MMA Record: 1-1
NFL Team(s): Washington Redskins, Cincinnatti Bengals
College(s): University of Colorado

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Jarrod Bunch

MMA Record: 0-1
NFL Team(s): New York Giants, Los Angeles Raiders
College(s): University of Michigan

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Johnnie Morton

MMA Record: 0-1
NFL Team(s): Detroit Lions, Kansan City Chiefs, San Francisco 49ers
College(s): University of Southern California

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Herbert Goodman

MMA Record: 19-11
NFL Team(s): Green Bay Packers
College(s): Graceland University

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Bob Sapp

MMA Record: 11-20
NFL Team(s): Chicago Bears, Minnesota Vikings
College(s): University of Washington

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