When his contract was not renewed by the WWE in 2004, Kevin Nash decided to join another company. That company was TNA.
In late-2004, Kevin Nash made his debut, along with Scott Hall, to help Jeff Jarrett retain his NWA Championship.
The following year, Nash got a shot at the NWA Championship, but lost. He, along with Sean Waltman and Diamond Dallas Page, began to feud against Jeff Jarrett and his Planet Jarrett faction.
Early on in the feud, Nash suffered an injury, and took time off to heal. When he returned in October, he continued his feud with Jarrett.
Just as Nash was set to face Jarrett for his NWA Championship at Bound For Glory, he began to suffer chest pains. He was offically replaced by Rhino at the event.
Nash returned to TNA in April 2006. Upon his return, Kevin Nash began an angle where he set out to defeat every X-Division wrestler on the roster.
He claimed that the division was a joke, and was out to set an example out of it. Many X-Division wrestlers that got in his way weren’t successful in defeating him.
As the angle began to die down, Nash started managing a few of the X-Division stars.
When Nash began managing Jay Lethal, he came up with the idea for Lethal to have a new gimmick. Nash’s idea had Lethal impersonating Randy Savage, which became very popular.
Nash was also manager of Chris Sabin and Alex Shelley. During that short period of time, the Motor City Machine Guns began to become very successful with Nash by their side.
In late-2008, Kevin Nash joined forces with Kurt Angle, Sting, Booker T, and Scott Steiner, to form the Main Event Mafia.
The faction was out to prove that they were the true stars of the company. When the homegrown TNA wrestlers heard that, they began to feud with the MEM.
For months, the Main Event Mafia and the TNA Originals were at war.
At the 2009 Victory Road, Nash won his first TNA title when he defeated AJ Styles to capture the Legends Championship.
Nash, shortly afterward, lost the title to Mick Foley. At Hard Justice, Nash recaptured the title, but later on lost it to Eric Young.
Shortly afterward, the Main Event Mafia faction disbanded.
At Final Resolution, Nash was a part of the Feast or Fired match. He successfully obtained a briefcase, which guaranteed him a shot at the Tag Team Championships.
On May 2010, Nash cashed in his Feast or Fired briefcase to win the Tag Team Championships. He and Scott Hall, who re-joined the company earlier that year, were the official champions.
After Hall and TNA had major problems, and was fired, he and Nash were stripped of the Tag Team Championships.
Months later, when Hulk Hogan began having too much control of TNA, Nash took notice, and disapproved.
In October 2010, Kevin Nash and Sting formed an alliance to go against Hogan’s faction. He and Sting were in no mood to be a part of the change that was happening, so they left the company (storyline-wise).
Though Sting returned to TNA months later, Nash never did. He was granted his release from the company, and once again made his way back to the WWE.