Australian Open champion Novak Djokovic retained his place as men’s world number one in the ATP rankings released Monday.

The Serb, who became the first player in the professional era to win three straight Australian Open titles with his defeat of Andy Murray on Sunday, stays on 12,920 points.

Briton’s Murray remains third behind Roger Federer of Switzerland, the man he beat in the semifinals in Melbourne.

Rafael Nadal of Spain has meanwhile slipped out of the world’s top four for the first time in more than seven years.

Nadal, who has been out of action with a knee injury since June, is due to return next week in Chile.

Nadal drops to fifth, with Spain’s David Ferrer moves up a place to fourth.

ATP top 10 as of January 28 (previous ranking in parenthesis): 1. (1) Novak Djokovic, Serbia, 12,920 points 2. (2) Roger Federer, Switzerland, 10,265 3. (3) Andy Murray, Britain, 8,480 4. (5) David Ferrer, Spain, 6,865 5. (4) Rafael Nadal, Spain, 5,400 6. (6) Tomas Berdych, Czech Republic, 4,680 7. (7) Juan Martin del Potro, Argentina, 4,210 8. (8) Jo-Wilfried Tsonga, France, 3,355 9. (9) Janko Tipsarevic, Serbia, 3,180 10. (10) Richard Gasquet, France, 2,720

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