In January, Arizona fired coach Rich Rodriguez without cause amid allegations of sexual harassment towards an administrative assistant and a hostile work environment. Now, the embattled coach is firing back with his own claim of extortion against his accuser. 

According to a response letter obtained by the Arizona Republic, Rodriguez claims his ex-assistant, Melissa Wilhelmsen, fabricated a tale of sexual harassment in order to extort $7.5 million from him. Rodriguez was fired on Jan. 2.

Here's what you need to know ... 

The $7.5 million is what Wilhelmsen initially filed a claim for in December

Rodriguez's camp says that his accuser tried to extort him for $7.5 million. If that number rings a bell, there's a reason. Wilhelmsen and her husband initially filed a $7.5 million claim against Rodriguez on Dec. 28, claiming that he sexually harassed her and created a hostile work environment. 

A lengthy list of accusations was published by the Star in January. In all, they detailed that Wilhelmsen was allegedly "forced to cover up Rodriguez's longtime relationship with his girlfriend" as a part of the so-called "Triangle of Secrecy" and that "eventually, Rodriguez began sexually harassing Wilhelmsen." 

Among the more explicit accusations is that Rodriguez once "embraced [Wilhelmsen], touched the side of her breast, and tried to kiss her" in January 2017. 

In a Twitter statement that has since been deleted, Rodriguez only admitted to an extramarital affair with a woman not affiliated with the university. He has denied all other allegations. 

Then, in January, Wilhelmsen submitted an additional $8.5 million claim against the university, saying it was liable for the coach's conduct because it knew about it and failed to properly respond. 

Rodriguez's attorneys say extortion attempts have been going on for a while

According to the newest letter obtained by the Star, attorneys for Rodriguez said the "extortion attempt dragged on for six weeks" last fall. Then, Wilhelmsen's attorney, Augustine Jimenez, demanded $7.5 million in compensation for her client on Dec. 10 with a Dec. 26 deadline -- the day before Arizona's Foster Farms Bowl appearance. 

"Demanding the payment the day before the Bowl Game was vicious, cut-throat, and explainable only as the ultimate threat to extort Coach and Mrs. Rodriguez of the $7.5 million," the filing said. 

According to an investigation from UA, the claims made by Wilhelmsen against Rodriguez "could not be substantiated." Rodriguez also claims he cooperated with the investigation and took -- and passed -- a polygraph test. 

This is not technically why Rodriguez was fired

Chalk it up to legal reasons, but Rodriguez was fired without cause. In a letter to students in January, Arizona said its decision was "based on several factors, including the direction and climate of our football program." At this point, the arguments are of the he said-she said variety. As such, the university still owes him $6.28 million according to the terms of his contract.

The program later hired former Texas A&M coach Kevin Sumlin.