Francis Bacon’s tribute to “the only man I ever loved” radiates with the unsettling emotional intensity that came to typify his work. With a nod to the landscapes of Vincent Van Gogh, it shows a small figure on the edge of woodland, darting across grass scorched by the searing African sun. It pulses with passion, ecstasy and pain – the highs and lows of his tumultuous relationship with his partner Peter Lacy, and his subsequent death in Tangier, Morocco.

Landscape Near Malabata, Tangier has resurfaced on the market for the first time in nearly 40 years and will go under the hammer at Christie’s in London on 7 March, with a pre-sale estimate of £15-20 million – more than 35 times its sale price when it was last auctioned in 1985 ($517,000, a world record for Bacon at the time).

The artist’s relationship with Lacy began after they met at the Colony Room in Soho in 1952. The former fighter pilot was a troubled man, who battled with alcoholism and reportedly had a violent streak. He once threw Bacon through a glass window, according to an account by art critic John Richardson, writing in the New York Review of Books. But that didn’t dim Bacon’s passion. He honoured Lacy in several other paintings, including the triptych, “Study for Three Heads” (1962), in the collection of MoMA, New York. Spinning with a “near centrifugal force”, as Katharine Arnold – the head of post-war and contemporary art at Christie’s Europe – puts it, Landscape Near Malabata, Tangier is a highly charged portrait of love and loss, in all its rich complexity.