I think either Boris Becker or Layton Hewitt. I think they were 17 years old.
As of December 2010, Rafael Nadal is the number 1 ranked male tennis player. As of January 2011, Caroline Wozniacki is the number 1 ranked female tennis player.
The best Swedish tennis player is probably, Robin Soderling, who stands currently ranked 5 in the world.
Yes.
Ille Nastase
At this time, the #1 Ranked player is Zhang Ji Ke from China
Novak Djokovic
Lleyton Hewitt (currently 34th in the world).
No he is not, Rafael Nadal is currently ranked #1 in the world.
John McEnroe
Marat Satin is a Russian politician and a retired tennis player. He is famous for winning two Grand Slam titles and was once ranked number one as the best tennis player in the world.
Rod Laver was a well known Australian tennis player who was ranked number one in the world from 1964 to 1970. He is the only tennis player to have won the Grand Slam twice.
Lleyton Hewitt, an Australian tennis player, is famous for ranking World No. 1 at age 20, making him the youngest male tennis player to ever rank World No. 1. He has competed in various tournaments as well.