This is the brilliant young honors student who was brutalized by Mad Men star Jon Hamm in a sadistic fraternity hazing ritual.

Seen here for the first time, Mark Allen Sanders was beaten with a paddle, dragged around a room by his genitals and had his pants set on fire.

Golden Globe winner Hamm was one of seven Sigma Nu brothers who tormented and humiliated Sanders when he was a young pledge at the University of Texas at Austin.

The young man was hit so hard during the warped 1990 initiation that he suffered a fractured spine and nearly lost a kidney.

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Hazing hell: Today Mark Sanders is a doctor and lawyer in Fort Worth Texas. But after he graduated high school in 1988 he entered the University of Texas at Austin and pledged the Sigma Nu fraternity. That's when he met John Hamm and his hazing hell began

Football hero: Jon Hamm the year he graduated from John Burroughs School in Ladue, Missouri and one year before his admission to University of Texas at Austin

Partners: Jon Hamm and Jennifer Westfeldt attended the "Girls" season four series premiere after party at The Museum of Natural History on January 5, 2015 in New York City.

Sanders subsequently withdrew from the university and sought counselling to cope with the shameful episode which resulted in a police inquiry and the fraternity chapter being disbanded.

Hamm, a sophomore, was identified as a ringleader and arrested in 1993, long before he became one of America's most recognizable actors playing boozy advertising exec Don Draper.

An assault charge was dismissed, however, and he completed a period of probation instead of receiving a conviction for hazing.

Our exclusive photos show Sanders in his senior year at Richland High School in North Richland Hills, Texas where he excelled in his studies, played for the basketball team and was treasurer of the school council.

Despite his ordeal at UT he was able to resume his education at Texas Christian University, before going to further institutions to study both law and medicine.

The 45-year-old lives now with his wife Anada, 41, and their two children in Fort Worth, where he works both as a doctor and an attorney specializing in medical malpractice and personal injury.

He has declined to speak publicly about his ordeal but the harrowing details are laid bare in court documents dating back more than two decades.

In a 1991 interview transcript obtained by Daily Mail Online, Sanders tells investigators with the Travis County's Attorney's Office how he suffered 'repeated beatings and assaults' at the hands of Sigma Nu 'actives'.

He also alleged that he and his fellow pledges were subjected to 'repeated confinements' in a series of tiny compartments carved into the frat building's foundations - including 'the pit', 'the hole' and 'the grave'.

Sanders listed Hamm as one of his chief tormentors, recalling how the future star ordered him to recite a six-page list of phrases pledges are told to memorize called the 'bulls*** list'

When Sanders forgot the last of Hamm's nicknames, which included MC Hammer and Young Bobby, he recalled how Hamm got "mad, I mean really mad'

Sanders told officials the worst of the hazing happened in the early hours of November 10, 1990 when he was summoned to the house and warned by Hamm: 'It’s going to be a long night.'

The junior was then allegedly subjected to two hours of brutal physical attacks as part of his fiery baptism into the fraternity.

Mark Sanders in his 1988 high school yearbook from Richland High School in North Richland Hills

He listed Hamm as one of his chief tormentors, recalling how the future star ordered him to recite a six-page list of phrases pledges are told to memorize called the 'bulls*** list'.

When he forgot the last of Hamm's nicknames, which included MC Hammer and Young Bobby, he recalled how Hamm got "mad, I mean really mad'.

Hamm and his frat cohorts' retribution was to spank Sanders repeatedly with a paddle.

'I'm hurting bad, I mean being hit right where the kidney is, it's killing me,' Sanders told his interviewers.

Hamm and another fraternity member then lifted Sanders up by his underwear, pulling it back and forth in a sawing motion.

'I don't know how far underwear stretches, I don't know how far I was off the ground,' he recalled.

'I was hurting really bad and I remember I was looking up at the ceiling and I was gritting my teeth and squinting my eyes ... it was sawing and it was hurting.'

Sanders told investigators how Hamm then led him to 'the pit' where he ordered him to do press-ups and pushed his face into the ground.

The distraught pledge felt someone, possibly Hamm, standing on his back.

Hamm is then supposed to have set fire to Sanders' pants and refused to let him pat the flames down, instead making him blow them out.

Finally he was led upstairs to the 'party room' when Hamm hooked the claw of a hammer underneath his testicles and pulled him around the room 'for at least a minute'.

Suave Don Draper has had to his own dark past on the hit show Mad Men. But for Jon Hamm, 'The hazing incident was an isolated incident,' said a friend

Despite his ordeal, Sanders was able to resume his education at Texas Christian University, before going to further institutions to study both law and medicine. The 45-year-old lives now with his wife in Fort Worth, where he works both as a doctor and an attorney specializing in medical malpractice and personal injury

In the wake of the hazing, Sanders fled to a friend's room to escape further brutality before eventually showing his bruises to fellow students.

He later claimed to have suffered nerve damage to his ribs, kidney spasms and a lineal spinal fracture

Sanders' horrified mother Margaret reported it to UT authorities, triggering a police investigation and prompting the fraternity to permanently close its UT chapter.

University records show Hamm, now aged 44, left the college at the end of the semester without a degree and returned to his hometown in Missouri.

Sanders later launched a lawsuit against Sigma Nu seeking 'unspecified actual and exemplary damages for willful and wanton misconduct'.

It was dismissed with the agreement of both parties, however, in 1993, possibly signalling that an out-of-court settlement had been reached.

That same year Hamm was arrested by the Austin Police Department but court documents show that in 1995 he received deferred adjudication, allowing him to avoid a criminal conviction by serving a period of probation.

His hazing shame went unreported for two decades until Star magazine broke the story last week in the midst of the final Mad Men season airing on AMC.

Hamm is yet to comment but a friend told Star: 'The hazing incident was an isolated incident in Jon's life. Since then, he's been strong enough to take steps to make himself a better person.'

Shame: The allegedly assault saw Hamm and seven other frat brothers set fire to the pledge and beat him with a paddle

Early career: Jon Hamm is pictured here on the 1996 show The Big Date - one year after he had his arrest warrant dismissed and six years after the alleged hazing incident

Three Sigma Nu members also pleaded no contest to charges of hazing, a misdemeanor, and were ordered to serve 15 to 30 days in jail.

They were subsequently allowed to complete a community service or work-release program instead.

Another member was convicted of a lesser hazing violation and fined $500.

Sander's attorney, Bill Whitehurst, did not return calls asking for comment.

A warrant was issued for Hamm's arrest in 1992 but the actor reached a plea deal with authorities in 1995 and the charges were dismissed.

He returned home to live with his family in Missouri and the actor - who recently emerged from a 30-day stint in a rehab facility - began his acting career.

A friend told Star that although shocking, 'The hazing incident was an isolated incident in Jon's life. Since then, he's been strong enough to take steps to make himself a better person.'