AceShowbiz - Tennis champions Serena Williams and Venus Williams' dad Richard is fighting dementia after suffering two strokes, according to documents filed as part of a court battle with his ex-wife.

The 77-year-old is involved in a legal dispute with his former partner Lakeisha Graham, 40, over the transfer of his home in Florida into her name.

According to court documents obtained by British newspaper The Sun, Richard, who coached his daughters in their early careers, is 'totally incapacitated to conduct any business."

The documents claim he suffered a series of strokes in 2016 which have left him barely able to speak and argue against Lakeisha unlawfully taking over his home.

"The complications after the stroke included inability to remember things which happened recently and incidents that happened years ago," testimony from his doctor, Monica Williams reads.

It also states that after the strokes his "muscles weakened," he has "problems speaking," and suffers from "cerebral vascular disease" and as a result could not conduct household business transactions.

Richard's lawyers claimed that Lakeisha forged his signature to change the mortgage deed on his property in Palm Beach into her name.

They claim an associate of Lakeisha's pretended to be him, so that she could borrow nearly $300,000 of equity on the house to start up a trucking business.

Richard is suing Lakeisha and David Simon, the lender who she borrowed from. The lender has demanded Richard disclose any gifts or income he receives from his daughters - a request he has refused.

The former tennis coach divorced from Serena and Venus' mother Oracene, in 2002. He married Lakeisha in 2010 and they divorced in 2017.