Former student sues fraternity after alleging hazing ritual left him with brain damage Blake Novacek is the son of famed Dallas Cowboys player Jay Novacek.

 -- The son of a legendary Dallas Cowboys player is now suing a University of Oklahoma fraternity, alleging that a hazing ritual left him with permanent brain damage so severe he can no longer remember his Social Security number.

According to lawyer Christopher Cooke, Blake Novacek, 20, whose father is former NFL tight end Jay Novacek, was subjected to numerous hazing incidents as he pledged the Gamma Phi chapter of Beta Theta Pi fraternity in the fall semester of 2015.

"Frankly, Blake's parents sent him off as a happy, healthy, well-adjusted boy and he came back a basket case," Cooke said.

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In court documents related to the lawsuit, Blake Novacek said that on Oct. 11, 2015, he was taken into Shane Musselman's room, where Musselman asked him to recite pledge facts.

When he was unable to do that, the complaint alleges, Novacek was struck in the stomach with a baseball bat, which caused him to "fall backwards and strike his head on a hard object, knocking [him] unconscious."

Cooke, his lawyer, said he was knocked unconscious around 2:30 a.m. and woke up at noon. According to the complaint, he awoke "on a couch in the fraternity house. His clothes had been laundered and were folded beside him."

The complaint alleged that after the incident, Novacek "was then confronted by Defendant Gavin Martindale, who told Plaintiff to keep his mouth shut about the hazing incident."

The lawsuit also includes Martindale and Musselman.

In a statement to the Fort Worth Star-Telegram, Musselman said: "The allegations against me are completely false, and I have no idea why they are being made. My family is hiring an attorney, and I intend to aggressively fight this suit and defend my reputation."

Martindale told OUDaily: "I'm bewildered by this lawsuit. The allegations are entirely untrue, and I'm mystified why this person is making these claims against me. To be honest, I'm angry about this, and I will be hiring a lawyer to aggressively defend me against these baseless accusations."

Cooke said Novacek had been diagnosed with traumatic brain injury, bipolar disorder and postconcussive syndrome, and is under the care of numerous doctors.

"All of this was brought on by the injury," Cooke said. "As time has gone on and he realizes the extent of his brain injury, he felt compelled to bring this lawsuit."

"Blake dropped out after the fall semester and he does not currently attend class," he said.

In a statement, the fraternity called Novacek’s allegations "false and inflammatory."

"We take any allegations of this character very seriously. However, since learning of this lawsuit, we have performed an initial investigation of Blake's allegations and have yet to uncover any evidence whatsoever which corroborates the substance of his claims. To the contrary, we have numerous witness accounts and other evidence which contradict Blake’s story and which question his credibility. Based on our investigations to date, we firmly believe Blake’s allegations are false and that his lawsuit is entirely without merit," the fraternity said.

"We note in particular that Blake's petition alleges the subject events occurred in the early morning of Sunday, October 11, 2015. In fact, no pledge or other fraternity activities occurred on that date. This date occurred during the weekend for the OU-Texas football game in Dallas, Texas, which was attended by nearly all the fraternity’s members and pledges, including Blake and the two individual members named in the suit.

‘Furthermore, while the plaintiff claims to have been in Norman the morning of October 11, 2015, he was actually in Arlington, Texas for the Dallas Cowboys game that day, as seen in the Instagram photograph below. Witness accounts confirm that he did not return to Norman until late that evening, and that neither he nor any other pledges were at the chapter house at any point during that day."

The University of Oklahoma said in a statement: "The university investigates every report of a violation of the Student Rights and Responsibilities Code. It would not be appropriate to comment on matters involved in pending litigation."

The fraternity's national office said in a statement: "Active litigation prohibits specific commentary on the matter, but Beta Theta Pi's position on hazing is unequivocal and unwavering: it is not condoned and it will not be tolerated. As such, and given that Beta has long been one of OU's hallmark student and alumni organizations, the General Fraternity is working closely with local alumni and undergraduate leaders in Norman to determine the basis for allegations they deem to be unfounded and without merit. We remain convinced that Beta's record of leadership and character will shed important light on these claims, and are committed to that truth, whatever it may be."

Cooke told ABC News today that after Novacek was injured, he lost the ability to process dates. Cooke said the Oct. 11, 2015 date was the closest in Novacek's mind, and that the incident had happened sometime shortly after the OU-Texas game.

Cooke said he plans to amend court papers.

ABC News affiliate WFAA-TV and ABC News' Jenn Metz and Emily Stanitz contributed to this story.