Grandmother's shock as portrait she thought was worth £500 turns out to be worth £5m plus

So she was astonished and delighted when the half-length portrait fetched £205,000 after a ferocious bidding war.

However she must be bitterly trying to come to terms with the fact that the picture which hung on her wall for 33 years is thought to be a Titian, worth upwards of £5million.

And somebody else - thought to be a London art dealer - will be enjoying the profits.

"I have nothing to say at all," said the 67-year-old grandmother. "It is a private matter."

Mrs Bryars and her husband David acquired the painting in 1974 when they bought Glen House - a seven-bedroom Georgian mansion in the Leicestershire village of Great Glen. It was hanging on the wall along with several other pictures which had belonged to the previous owner, the late Colonel John Puxley White Jamie.

After Mr Bryars died three years ago, his widow sold the house and some of its contents for £1.4million.

She put the bearded man up for sale earlier this month at Mark Gilding's small, family-run auction house in Market Harborough.

The painting, given an estimate of £300 to £500, was billed as an "18th-Century Continental school, half-length portrait of an aesthete".

In fact, it is thought to have been painted by Tiziano Vecelli, better known as Titian, in Venice between about 1510 and 1520. Its style is very similar to Titian's Portrait of a Young Man, worth £55million, which was previously hung in the National Gallery on loan from the Earl of Halifax.

Christopher Foley, a dealer, said of the Leicestershire sale: "That price suggests that two people knew what it was: one of them perhaps young and clever, with a budget of £200,000. And someone else."

Old Master dealer Simon Dickinson said: "It looks like perfect early Titian . . . the handling looks like early Titian, the way the shirt is painted, and the face. The ear looks a bit clumsy, as if it's been repainted. But it looks jolly good."

Mrs Bryars, whose late husband is believed to have made his fortune in the textile trade, now lives in a smart courtyard cottage in a village near Great Glen, close to her daughter and her family.

She added: "All I will say is that we will now be taking a close look at all the art that was in that house." Asked where she had hung the painting, she tersely replied: "It hung in various places in the house but I have nothing further to add. It is out of our hands now."

Mr Gilding was doing his best to remain positive yesterday, but he admitted the bidding frenzy had come as a "complete shock".

He said: "We maintain that the painting was a very good reproduction of an original but not an old master from the 16th century. It is interesting that the bidding stopped when we passed £200,000. If art experts had been certain this was a Titian then I suspect the price would have been even higher.

"My hunch is that the buyer will be disappointed and discover that it is really not worth what they think it is. Our considered opinion was that it was a copy of an old master painting and we are sticking to that."