Mikhail Prokhorov, believed to be the richest man in Russia, has agreed to spend US$200 million to secure an 80 per cent stake in the New Jersey Nets, part-owned by rap star Jay-Z, and 45 per cent of the Barclays Center.

The 6'7 Prokhorov, himself a keen basketball player, has invested three months before the deadline for Ratner to break ground on the arena or lose financing through tax-exempt New York State bonds. Barclays also has the right to renege on its US$400 million, 20-year naming-rights deal for the arena if construction hasn’t started by that date.

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"This partnership will ensure the successful completion of a world-class entertainment venue in Brooklyn, the relocation of the NBA Nets basketball team and the economic and housing benefits of the Atlantic Yards Project," said a joint statement from Forest City Ratner Cos, Nets Sports & Entertainment and Prokhorov's Onexim Group.

Prokhorov said: "We must change the model of basketball development in Russia using super-modern systems of coaching. The base for such development should be a strong youth basketball league."

The New York Times quoted an unidentified executive saying that Prokhorov has joked that he will be "the only NBA owner who can dunk."

NBA commissioner David Stern added: "Interest in basketball and the NBA is growing rapidly on a global basis. We are especially encouraged by Mr. Prokhorov’s commitment to the Nets and the opportunity it presents to continue the growth of basketball in Russia."