Roger Federer maintained his big lead in the men's tennis rankings issued on Monday by the ATP.

The Swiss Federer has 10,690 points to lead from Serb Novak Djokovic (7,390) and Spain's Rafael Nadal (6,980), who won a sixth Monte Carlo Masters title on Sunday.

The Monte Carlo finalist Fernando Verdasco of Spain rose from 12th to ninth place.

On the SA front, there was good news for Kevin Anderson as he reached a career high of 85 - up from 103 the week before - thanks to a win on the Challenger Tour at Baton Rouge, Los Angeles.

It is also the first time he has been back in the world's top 100 since June 2008.

ATP top 10 as of April 19 (previous ranking in parenthesis):
1. (1) Roger Federer, Switzerland, 10,690
2. (2) Novak Djokovic, Serbia, 7,390
3. (3) Rafael Nadal, Spain, 6,980
4. (5) Juan Martin del Potro, Argentina, 5,725
5. (4) Andy Murray, Britain, 5,485
6. (6) Nikolay Davydenko, Russia, 5,335
7. (7) Andy Roddick, United States, 4,780
8. (8) Robin Soderling, Sweden, 4,595
9. (12) Fernando Verdasco, Spain, 3,145
10.  (10) Jo-Wilfried Tsonga, France, 3,005