Jamie Murray's five-week reign as world doubles number one will end on Monday following defeat at the Madrid Open.
The Scot and Brazilian Bruno Soares were beaten 6-4 7-6 (7/4) in the second round by Finn Henri Kontinen and Murray's former partner John Peers.
Murray took over from Brazilian Marcelo Melo at the top of the standings following the Miami Open, becoming the first British player ever officially to be ranked world number one.
But the points difference was small and it was always likely to prove a tough position to defend.
He staved off the immediate threat by reaching the final of the Monte Carlo Masters last month but Murray and Soares' loss on Thursday means it is a three-way fight between Melo, France's Nicolas Mahut and Romanian Horia Tecau to replace him.
Source: PA
