John Wisniski, Jr. is an American professional wrestler, better known as Greg "The Hammer" Valentine. He is the son of wrestler Johnny Valentine. In the course of his career, which has spanned over four decades, Valentine has held more than 40 championships, including the NWA United States Heavyweight Championship and the WWE Intercontinental Championship. An alumnus of WWE and World Championship Wrestling, he was inducted to the WWE Hall of Fame in 2004.

Filmography

• 2025Midnight Massacre — Caepio
• Biography: WWE Legends — Greg "The Hammer" Valentine
• WWE's Most Wanted Treasures — Greg "The Hammer" Valentine
• 2020Chris Jericho's 30th Anniversary Celebration — Greg "The Hammer" Valentine
• Undertaker: The Last Ride — Greg Valentine (archive footage)
• All Elite Wrestling: Dynamite — Greg Valentine
• 2016WWE: The U.S. Championship: A Legacy of Greatness — Greg 'The Hammer' Valentine (archive footage)
• 2011JCW Legends and Icons
• 2006WWE: The History Of The WWE Championship
• 2005World Wrestling Legends: 6:05 - The Reunion — Greg Valentine
• 1999Heroes of Wrestling — Greg "The Hammer" Valentine
• 1997WCW World War 3 1997 — Greg "The Hammer" Valentine
• AWF Warriors of Wrestling — Greg "The Hammer" Valentine
• 1994WWE Royal Rumble 1994 — Greg "The Hammer" Valentine
• Raw — Greg "The Hammer" Valentine
• 1993WWE Survivor Series 1993 — The Blue Knight
• 1992The Immortal Hulk Hogan — Greg Valentine
• 1992WCW Beach Blast — Greg "The Hammer" Valentine
• 1992WCW Clash of The Champions XX: 20th Anniversary — Greg "The Hammer" Valentine
• 1992WCW WrestleWar 1992 — Greg "The Hammer" Valentine
• 1992WWE Royal Rumble 1992 — Greg "The Hammer" Valentine
• 1992WWE SuperTape: Volume 5 — Greg "The Hammer" Valentine
• 1991WWE Funniest Moments — Greg "The Hammer" Valentine
• 1991WWE Mega Matches — Greg "The Hammer" Valentine
• 1991WWE Rampage '91 — Greg "The Hammer" Valentine
• 1991WWE Royal Rumble 1991 — Greg "The Hammer" Valentine
• 1991WWE SummerSlam 1991 — Greg "The Hammer" Valentine
• 1991WWE Superstars & Stripes Forever: The March to WrestleMania VII — Greg "The Hammer" Valentine
• 1991WWE U.K. Rampage 1991 — Greg "The Hammer" Valentine
• 1991WWE WrestleFest '91 — Greg "The Hammer" Valentine
• 1991WWE WrestleMania VII — Greg "The Hammer" Valentine
• 1990Battle of the WWE Superstars — Greg Valentine
• 1990WWE Hottest Matches — Greg "The Hammer" Valentine
• 1990WWE Royal Rumble 1990 — Greg "The Hammer" Valentine
• 1990WWE SuperTape: Volume 2 — Greg "The Hammer" Valentine
• 1990WWE Survivor Series 1990 — Greg "The Hammer" Valentine
• 1990WWE The Ultimate Challenge Special: The March to WrestleMania VI — Greg "The Hammer" Valentine
• 1990WWF/AJPW/NJPW Wrestling Summit
• 1990Wrestling Superheroes — Greg "The Hammer" Valentine
• 1989Demolition: Witness the Power — Greg "The Hammer" Valentine
• 1989Fan Favorites — Greg Valentine
• 1989The Best of the WWF: volume 20 — Greg "The Hammer" Valentine
• 1989The Ultimate Warrior — Greg "The Hammer" Valentine
• 1989WWE Los Angeles Wrestling: January '89 — Greg "The Hammer" Valentine
• 1989WWE Maple Leaf Wrestling: April '89 — Greg "The Hammer" Valentine
• 1989WWE Royal Rumble 1989 — Greg "The Hammer" Valentine
• 1989WWE SummerSlam 1989 — Greg Valentine
• 1989WWE Survivor Series 1989 — Greg "The Hammer" Valentine
• 1989WWE WrestleMania V — Greg "The Hammer" Valentine
• 1989WWE Wrestling at The Meadowlands: May '89 — Greg "The Hammer" Valentine
• 1988Brutus "The Barber" Beefcake — Greg "The Hammer" Valentine
• Clash of the Champions — Greg "The Hammer" Valentine
• 1988Macho Madness — Greg "The Hammer" Valentine
• 1988The Best of the WWF: volume 16 Around the World — Greg "The Hammer" Valentine
• 1988WWE Los Angeles Wrestling: December '88 — Greg "The Hammer" Valentine
• 1988WWE Maple Leaf Wrestling: April '88 — Greg "The Hammer" Valentine
• 1988WWE Maple Leaf Wrestling: July '88 — Greg "The Hammer" Valentine
• 1988WWE Survivor Series 1988 — Greg "The Hammer" Valentine
• 1988WWE U.K. Rampage 1988 — Greg "The Hammer" Valentine
• 1988WWE WrestleMania IV — Greg "The Hammer" Valentine
• 1988WWE Wrestling at The Meadowlands: September '88 — Greg "The Hammer" Valentine
• 1987Bob Uecker's Wacky World of Sports — Greg "The Hammer" Valentine
• 1987The Best of the WWF: volume 10 — Greg "The Hammer" Valentine
• 1987The Best of the WWF: volume 11 — Greg "The Hammer" Valentine
• 1987The Best of the WWF: volume 14 — Greg "The Hammer" Valentine
• 1987WWE Houston Wrestling: December '87 — Greg "The Hammer" Valentine
• 1987WWE Houston Wrestling: October '87 — Greg "The Hammer" Valentine
• 1987WWE Maple Leaf Wrestling: January '87 — Greg "The Hammer" Valentine
• 1987WWE Maple Leaf Wrestling: June '87 — Greg "The Hammer" Valentine
• 1987WWE Survivor Series 1987 — Greg Valentine
• 1987WWE WrestleMania III — Greg "The Hammer" Valentine
• 1987WWE Wrestling at The Meadowlands: January '87 — Greg "The Hammer" Valentine
• 1987Wrestling's Most Embarrassing Moments — Greg "The Hammer" Valentine
• 1986Inside the Steel Cage — Greg "The Hammer" Valentine
• 1986Ricky "The Dragon" Steamboat — Greg "The Hammer" Valentine
• 1986Tag Team Champions — Greg Valentine
• 1986The Best of the WWF: volume 5 — Greg "The Hammer" Valentine
• 1986The Best of the WWF: volume 7 — Greg "The Hammer" Valentine
• 1986The Best of the WWF: volume 9 — Greg "The Hammer" Valentine
• 1986The British Bulldogs — Greg Valentine
• 1986WWE Grudge Match — Greg "The Hammer" Valentine
• 1986WWE Houston Wrestling: October '86 — Greg "The Hammer" Valentine
• 1986WWE The Big Event — Greg "The Hammer" Valentine
• WWF Superstars — Greg "The Hammer" Valentine
• WWF Wrestling Challenge — Greg Valentine, Greg "The Hammer" Valentine
• 1986WrestleMania II — Greg "The Hammer" Valentine
• 1985Hulkamania 1 — Greg Valentine
• 1985Most Unusual Matches — Greg "The Hammer" Valentine
• 1985The Best of the WWF: volume 4 — Greg "The Hammer" Valentine
• 1985The WWF's Amazing Managers — Greg 'The Hammer' Valentine
• 1985WWE Maple Leaf Wrestling: April '85 — Greg "The Hammer" Valentine
• 1985WWE Maple Leaf Wrestling: December '85 — Greg "The Hammer" Valentine
• 1985WWE Maple Leaf Wrestling: October '85 — Greg "The Hammer" Valentine
• 1985WWE Maple Leaf Wrestling: September '85 — Greg "The Hammer" Valentine
• WWE Saturday Night's Main Event — Greg Valentine, Greg "The Hammer" Valentine
• 1985WrestleMania — Greg "The Hammer" Valentine
• 1984NWA Boogie Jam — Greg Valentine
• Tuesday Night Titans — Greg "The Hammer" Valentine, Greg Valentine
• 1984WWE Maple Leaf Wrestling: October '84 — Greg "The Hammer" Valentine
• 1984WWE Maple Leaf Wrestling: September '84 — Greg "The Hammer" Valentine
• 1984WWE The Brawl to End it All — Greg "The Hammer" Valentine
• 1983NWA Starrcade 1983 — Greg "The Hammer" Valentine
• 1983NWA The Final Conflict — Greg Valentine
• 1983NWA The Race to Starrcade — Greg Valentine
• WCW Arena Shows — Greg Valentine
• 1982NWA Sam Muchnick Retirement Show — Greg Valentine
• Mid-Atlantic Championship Wrestling — Greg Valentine
• WWF All-Star Wrestling — Greg Valentine, Greg 'The Hammer' Valentine
• WWE Old School — Greg Valentine, Greg "The Hammer" Valentine

Appearances as themselves (10)

• 2019350 Days — Self
• 2019Headstrong — Self
• 2015At What Cost? Anatomy of Professional Wrestling — Himself
• 2015Behind the Ropes: The Greatest Fraternity in the World — Himself
• 2014WWE: 150 Best Pay-Per-View Matches, Vol 1 — Himself
• 2012WWE: Starrcade - The Essential Collection — Himself
• 2011Timeline The History of WWE – 1985 – As Told By Greg Valentine — Himself
• 2008WWE: The History Of The Intercontinental Championship — Himself
• 2005The Greatest Wrestling Stars of the '80s — Self
• 2004WWE Hall of Fame 2004 — Self