Wimbledon champion Andy Murray has slipped to 7th in the world rankings after a quarter-final defeat to Croat Marin Cilic in the AMRO World Tennis Tournament in Rotterdam last week.
The Scot, who has been hampered by inconsistencies in the early embers of the new season, lasted just 71 minutes before being beaten in straight sets 6-3 6-4.
It was a defeat that allowed Tomas Berdych, who ended a 16 month wait for a title with victory in the Netherlands, to leapfrog Murray into 6th place in the rankings.
David Ferrer was another climber, rising by one place to 4th after becoming the first man to win three straight Copa Claro titles in Argentina.
His victory meant that 2009 US Open champion Juan Martin Del Potro dropped to 5th. The Argentine was beaten by Ernests Gulbis in the quarter-finals of the tournament in Rotterdam.
Former world number one and 17-time Grand Slam champion Roger Federer was another casualty of the newest rankings, sliding to 8th, with his powers showing new signs of depleting. The Swiss star has not won a title since his victory in Halle last June.
However, he still stands above French pair Richard Gasquet and Jo-Wilfried Tsonga, who stand in ninth and tenth respectively.
The front trio of Rafael Nadal, Novak Djokovic and Australian Open champion Stanislas Wawrinka remain intact at the summit of the men’s game.
World No.1 Nadal will be making his comeback from injury at the Rio Open, which commences at midnight tonight.
The newest rankings were released by the ATP tour on Monday.
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