Titian 'copy' turns out to be a real work of art

For years, a painting in the National Gallery was labelled as a 16th-century copy created after Titian and rarely seen by the public, having been variously relegated to the lower galleries and conservation studios.

Now the same painting – a portrait of a man – is being seen in a new light. Having undergone extensive cleaning and restoration, it has been attributed to the revered Renaissance master and given pride of place in one of the main upper galleries.

The National Gallery confirmed that the picture had been upgraded and credited to "the greatest painter of 16th-century Venice". A spokeswoman said: "He is thought to have painted the work in the 1520s... It has been in many rooms since joining the National Gallery collection in 1924."

The gallery declined to give further details ahead of an official announcement later this month. But the painting has already taken its place, with its new label, in Room 12 alongside jewels of the gallery's collection – masterpieces such as Titian's Bacchus and Ariadne (1523-24) and Palma Vecchio's Portrait of a Poet (c.1516).

The new addition to the room is thought to depict another poet, the Italian Girolamo Fracastoro, whose most famous work was a poem on syphilis. The theory of his identity is reinforced by an inscription with his name on a strip of paper once stuck on the canvas.

The painting came to the National Gallery as part of a bequest made in the 1920s by Ludwig Mond, the chemist who founded Imperial Chemical Industries. The collection included some of the gallery's most outstanding Renaissance paintings, most famously Raphael's Crucified Christ (The Mond Crucifixion).