BBC bosses have criticised Sir Cliff Richard over the lawyers' bills he has run up after complaining about reports naming him as a suspected sex offender and taking High Court action.
Bosses say a trial is unlikely to be staged this year but figures show the singer has already run up legal costs of more than £800,000.
A barrister leading the BBC's legal team outlined concerns at a preliminary High Court hearing in London on Thursday,
Gavin Millar QC told a judge, in a written submission, that costs incurred were "grossly unreasonable" and "on any view ... disproportionate".
The BBC could be ordered to pick up Sir Cliff's lawyers' bills if he wins the battle.
Mr Justice Mann is overseeing the latest in a series of preliminary hearings in London.
Sir Cliff was not at the hearing which is due to end on Friday.
His lawyers have provided explanations for bills.
The singer has taken legal action against the BBC, and South Yorkshire Police, over coverage of a raid at his apartment in Sunningdale, Berkshire, in August 2014.
His lawyers say he suffered ''profound and long-lasting'' damage.
BBC editors have said they will ''defend ourselves vigorously''.
A spokeswoman said the BBC had reported Sir Cliff's ''full denial of the allegations at every stage''.
South Yorkshire Police have apologised ''wholeheartedly for the additional anxiety caused'' by the force's ''initial handling of the media interest'' in its investigation into the singer.
Lawyers say in late 2013 a man made an allegation to the Metropolitan Police - saying he had been sexually assaulted by Sir Cliff at Sheffield United's Bramall Lane football stadium when a child in 1985.
Metropolitan Police officers passed the allegation to South Yorkshire Police in July 2014.
Sir Cliff denied the allegation ''as soon as it was brought to his attention'', and in June 2016 prosecutors announced that he would face no charges.
A spokesman for Sir Cliff said outside court: "Sir Cliff Richard incurred these costs and expenses over more than a two year period, we say as a direct result of the actions of South Yorkshire Police and the BBC.
"Ultimately it will be down to a judge to decide whether or not he should recover such costs and expenses in full or in part, or at all."
The hearing has ended for the day and continues on Friday.