The outspoken owner was being interviewed in the latest episode of the Knees Up Mother Brown Podcast, when he responded to a question as to whether the club were interested in signing Queens Park Rangers star Austin.
'No ligaments, big gamble'
Sullivan implied that the England man was too big a gamble for West Ham given what he had heard about his injury history.
“He (Austin) failed a medical at Hull a couple of years ago," Sullivan said in the KUMB interview.
"They say he has no ligaments in his knee, who knows?
"To sign a player for £15m is a big risk. He could go on for years but knowing our luck his knee will go in his first game and that’s the end of it."
'An outrageous slur'
When Sullivan's words were made public on Thursday it provoked an angry response from the player himself, who took to social networking site Twitter to issue a statement.
In it he lashed out at Sullivan calling his comments 'an outrageous slur'.
And now Ferdinand, who played 14 times for West Ham when they were relegated in 2003, has hit back at Sullivan too, pointing out he was the man who brought Demba Ba to the Premier League despite issues surrounding his knees.
Hypocrite Sullivan has a short memory
“His (Austin's) fitness has never been an issue for us and he has not missed a game for us over the last couple of years because of it,” the ex Tottenham Hotspur star told the Guardian.
“They said Demba Ba had a dodgy knee. West Ham signed him and he didn’t miss a game for them.
“If they don’t think Charlie would be a good fit for West Ham then that’s their prerogative. Everyone is entitled to their opinion.
"But to question his record or his fitness when he hasn’t missed a game for us over the last couple of years is a different matter.”
As a former Premier League striker and West Ham player, Ferdinand's words carry plenty of weight.
And his point about Ba is a salient one.
Back in 2011, with West Ham struggling for Premier League survival under the hapless Avram Grant, Sullivan signed Ba on a three-year deal after he had failed a medical at Stoke City.
The issue was reportedly to do with a knee problem but Ba went on to prove a shrewd signing scoring seven goals in 12 games.
His form earned him a move to Newcastle United when the Hammers were relegated and later Chelsea.