One of only a handful of Michelangelo drawings left in private ownership will go on display ahead of its sale next week.
Study of a Male Torso, which dates from the 1550s, is expected to fetch more than €3 million at Christie's in New York.
It has appeared on the open market only once before, when it set a world auction record for an Old Master Drawing.
The sketch survived Michelangelo's determined destruction of many of his drawings in bonfires.
Of the tens of thousands he produced over seven decades, little more than 600 survive, and the overwhelming majority have long been in the great public collections of Europe.
Michelangelo's 16th Century biographer Giorgio Vasari suggested the artist was afraid his creative struggles would be revealed through scrutiny of his working drawings. He may also have been paranoid that his legendary inventiveness would be copied by unscrupulous fellow artists.
The drawing being sold on Tuesday was part of a collection belonging to John Malcolm of Poltalloch.
When he died in 1893 much of the collection was bought by the British Museum, but the Study of a Male Torso remained in the family until it was bought by the current private owner for €260,000 in 1976.
Christie's said it could depict the ageing artist musing on his own mortality, a mood reflected in his famous mystical poems of the same period.
It is one of a small number of drawings by the artist which seem to relate to the figure of Christ for a Pieta composition - a painting or sculpture of the Virgin Mary holding and mourning over the body of Jesus - although no commission of this type is recorded.