Goodbye Juju

For a spunky teenager, Justine Henin had the most explosive of entrances into the world of pro tennis. At 16, nine years ago, she won her WTA debut tournament, the Belgian Open. She retired last night, aged 25, just weeks before the French Open, which she'd won four times.
It took a defeat to Serena Williams in the quarters of the Sony Ericsson Open, a retirement due to knee injury in the Family Circle Cup and then a first ever defeat to Dinara Safina in the German Open for Justine to decide to pull the plug. The knee was never gonna get better.
Sad day for tennis, but I can't remember when a player ever retired while ranked number one in the world.