And now lot 403: the Old Master worth £5m. Do I hear £300?

The painting was just one among a motley selection up for auction in Market Harborough, LE16, UK, Leicestershire, England. There was a sentimental picture of gambolling terriers ("English school, estimate £150-200"); cottagey views; harvest scenes; Scottish waterfalls: a rollcall of pastiches, non-entities and plain old fit-for-the-dustbin disasters.

And then there was lot 403. Described in the auctioneer's catalogue as "18th-century continental school, half-length portrait of an aesthete", it depicted a black-clad, bearded man, his face half turned to the right, a rather distant, soulful expression in his eyes.

The estimate on the picture was £300-£500. When its turn came last Tuesday at Gilding's Antique Auctioneers and Valuers - a small, family-run auction house that holds about 45 sales per year - something truly extraordinary happened. "The atmosphere in the room became very tense - the bidding just went on and on," said the auctioneer, Mark Gilding. The final hammer price was £205,000.

And, enormous as the figure may seem, that's just the start of it. The London fine art trade is now abuzz: this painting is very probably a Titian, painted in Venice between about 1510 and 1520. And as such, its real market value is likely to be upwards of £5m.