Serena and Venus Williams' father Richard is battling dementia, his doctor has revealed in court papers.

Richard Williams was said to have been left with irreparable 'brain damage' after suffering two strokes and has difficulty speaking, according to court documents filed in Florida.

The 77-year-old is said to be 'totally incapacitated to conduct any business', the recently unsealed documents state.

The claims were revealed during a protracted legal battle between Williams and his estranged wife Lakeisha, 40, over the transfer of his home in Florida into her name.

Testimony from his own doctor described in newly revealed filings Williams' 'inability to remember things' and that his 'muscles weakened'.

He suffered a series of strokes in 2016 which have left him barely able to speak in order to argue that his ex-wife has unlawfully taken over his home, the documents claim.

Serena Williams (right) celebrates with her father Richard Williams and sister Venus Williams after her Ladies' Singles final match against Agnieszka Radwanska at Wimbledon in 2012

Richard Williams accused wife Lakeisha (pictured with their six-year-old son Dylan) of filing mortgage papers where his signature was forged

In the Florida documents the doctor explains how the stroke affected his 'brain function', according to the Sun.

DailyMail.com previously revealed how the tennis coach claimed in court papers against his Lakeisha that his signature was forged on mortgage papers which transferred the property to her.

His lawyers said if he did sign the documents his 'mental capacity was compromised' from the strokes and he did not understand what he was signing.

Williams, of West Palm Beach, Florida filed for divorce from Lakeisha in 2017 after they married in 2010. The couple have a six-year-old son Dylan, born in July 2012.

In 2016, it was reported he had suffered one stroke, but court papers show he in fact has had two.

Williams also suffers from a neurological condition which affects his mouth and means he can only speak through his son 45-year-old Chavoita LeSane, who has now been given power of attorney.

In an ongoing lawsuit, Williams claims Lakeisha transferred the deed for one of his homes in Palm Beach, Florida, to herself without his permission and then took out a $152,000-mortgage from an associate using Williams' forged signature.

The messy court battle with Lakeisha appears to have taken a serious toll on Williams' health.

Richard Williams, father of Venus Williams and Serena Williams (pictured right after winning a ournament in New Zealand earlier this month), is embroiled in a legal battle with his estranged wife, Lakeisha

Venus Williams shared a pictured of her practice with her father on Instagram yesterday before heading to China for a tournament

In court papers obtained by DailyMail.com, Richard Williams' attorneys say if he did sign the mortgage documents his 'mental capacity was compromised' from the strokes he had suffered and wife Lakeisha knew Richard did not understand what he was doing

In further document, Williams' medical condition was revealed 'difficult to use the right words' and mixes up present events with the past.

Dr Monica Walker's statement reads: 'As you are well aware, you suffered damage to your brain tissue during a stroke.

'The complications after the stroke included inability to remember things which happened recently and incidents that happened years ago.

'You will remember, immediately after the stroke, your muscles weakened and slowly you were able to regain strength. You also have problems speaking and finding the right word to use.

'You have recovered from problems forming your words. However, you have not recovered from what is called dementia.

Williams suffered from what was described as 'cerebral vascular disease and stroke' which left him 'easily confused'.

It read: 'Your ability to do household business transactions such as writing checks, paying bills, and maintaining records is lost. You still at times find it difficult to use the right words. This is all part of cerebral vascular disease and stroke.

Richard Williams with his daughter Venus pose for a photograph 1991 in Compton, California, in 2000

Williams watching his daughter Serena Williams play Sabine Lisicki in California in 2011

Richard Williams claims in court documents his signature was forged on mortgage papers

Richard Williams' attorneys describe how his son Chavoita LeSane acts as his translator after two strokes and a 'neurological condition' affected his speech

'When I spoke with you concerning legal matters and your level of judgement during any household or business transactions, you stated you were unable to do any tasks relating to business.

'You stated your wife handled all the household business because you get confused easily.

'Your mental state since the first stroke includes loss of recent and remote memory and increased confusion during times of increased demands for concentration.'

According to previously filed court documents, Williams believes Lakeisha either used his forged signature when switching the mortgage deeds or, offers another theory, while his 'mental capacity was compromised', he signed the documents without knowing what they were.

Due to his health at the time, the papers claims, Williams does not know what she did.

In 2017, Williams filed another lawsuit accusing his estranged wife of stealing his social security checks, where the pair used to live, according to documents filed in Palm Beach County.