According to court documents, Wendy Haskell alleges Moon made "unwanted and unsolicited" sexual advances as part of her role as his assistant.
"According to the new lawsuit, Moon required Haskell to stay in his hotel room during business trips, sleep in the same bed and wear "skimpy thong lingerie bottoms" as nightclothes".
A woman claimed Moon grabbed her crotch during a business trip to Seattle earlier this year, required her to wear thong underwear and share his bed during other business trips and pulled off her bathing suit after slipping a drug into her drink during a business trip to Mexico in October.
The lawsuit says that, on October 6, Haskell told Moon that "while she loved working at S1M, she was very uncomfortable with the travel sleeping arrangements and shower protocol".
A publicist for Moon's company, Sports 1 Marketing of Irvine, California, did not return phone calls or an email seeking comment.
Having retired from the National Football League in 2000, Moon has been a member of the Seahawks' broadcast team since 2004.
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After a sterling career at the University of Washington, Moon became a pro football legend for his productivity as well as his longevity.
Hours after it was noted that Pro Football Hall of Fame quarterback and current Seattle Seahawks broadcaster Warren Moon was being sued for sexual harassment, the organization has granted Moon a leave of absence.
Moon spent three seasons with the Vikings from 1994 to 1996 after Minnesota acquired the quarterback in a trade with the Houston Oilers.
Though Moon has been accused of sexual misconduct and domestic abuse before, this is the first time he has gone under the spotlight in the post-Weinstein era of hyper-awareness towards powerful men sexually harassing and assaulting women.
She says in the lawsuit that "Moon had a dark and twisted side that commanded far more than just executive assistant services from his newly hired employee".
Moon was accused of striking his then wife, Felicia Moon, on the head with an open hand and choking her to the point that she nearly lost consciousness before she escaped from the couple's home in July 1995. "She had no idea that her job duties were going to involve that kind of perverse protocol". They divorced in 2001.