Leko substitutes Anand in Nanjing

Official website: http://www.chess-pearlspring.com/www/chess_pk/2009/en/index.htm

Peter Leko (born September 8, 1979 in Subotica, Yugoslavia) is a Hungarian chess player. He became a grandmaster in 1994 at the age of 14 years (a world record at the time). In the January 2009 FIDE list, he has an Elo rating of 2751, making him number nine in the world, and Hungary’s number one. His best rating was number four, first achieved in April 2003.

　　Early life
　　Leko was a chess prodigy and became a Grandmaster at age 14, then the youngest ever.
　　He is the son-in-law of Armenian grandmaster Arshak Petrosian.
　　World Championship results

　　In 2002 Leko won the Candidates Tournament to qualify as the challenger to Vladimir Kramnik for the Classical World Chess Championship 2004. (The World Chess Championship was split at the time, but most of the strongest players participated, the most notable exceptions being the world’s top two, Garry Kasparov and Viswanathan Anand). After several delays, the match was held from September 25 – October 18, 2004, in Brissago, Switzerland. Leko led by a point with just one game left to play. Kramnik managed to win the last game, tying the match 7–7, which entitled him to remain the reigning “classical” world champion.

　　In October 2005, Leko played for the FIDE World Chess Championship title in San Luis, Argentina, and was ranked fifth with 6.5 points. For more information, see FIDE World Chess Championship 2005.

　　In May-June 2007 Leko played in the Candidates Tournament for the World Chess Championship 2007. He won his matches against Mikhail Gurevich and Evgeny Bareev, to qualify for the eight-player championship tournament. In the championship he finished fourth out of eight.

　　Chess960

　　In 2001, Leko narrowly defeated Grandmaster Michael Adams in an eight game Fischer Random Chess (Chess960) match played as part of the Mainz Chess Classic. As a result, Leko was hailed by many as the first Fischer Random Chess world champion. This claim is not universally accepted, since there were no open qualifying matches. Many do accept the claim, however, since this was also true of the first orthodox world chess champion titleholders, and both players were in the top five in the January 2001 world rankings for orthodox chess.

Here is more info on Leko.