The America's Got Talent host is said to have taken out five motions hoping to persuade a judge to dismiss the libel case against her, filed by Lorraine Gilles, according to the Mirror.
Mel, 42, made the claims that 25-year-old Lorraine was one of the main reasons her marriage to film producer Stephen Belafonte broke down.
She alleged that the pretty blonde from Germany had an affair with Stephen and terminated a pregnancy after their secret trysts. The nanny heavily denied the allegations and filed a lawsuit against Mel for libel.
Mel's legal team now hope to convince Judge Dalila Lyons of Los Angeles Superior Court to rull the case null and void, saving her millions in fees.
An LA legal source told the paper: 'Mel has spent thousands of pounds on lawyers to try and shut down the nanny.
'She knows a full-blown trial could cost her vast amounts in legal fees alone. If she loses it would be unthinkable for her financial status.
'Mel has told the judge her accusations about Lorraine were no smear campaign as she did not act in “reckless disregard”'.
The America's Got Talent judge filed for divorce from Belafonte, the father of her youngest child, in March after 10 years of marriage.
She successfully obtained a restraining order against him after alleging abuse.
The spousal support hearing is slated for the end of this month.