National champion Surya Shekhar Ganguly and GM Dibyendu Barua also bowed out of the World Chess Championship.
Grandmaster Koneru Humpy beat Ekaterina Kovalevskaya of Russia in the second game to push the match into tie-breaker.
The Indian Grandmaster meets Cecile Van Der Merwe of South Africa in her opening match of the tournament.
Topalov, with his unsurpassable score of 9.5 points from 13 games has emerged the New World Chess Champion, 2005.
Viswanathan Anand thrashed Hungary's Peter Leko in the 12th game of the World Chess Championship on Wednesday.
The Indian ace has 4.5 points with six rounds remaining in the World chess championship. Vaselin Topalova, with seven points, leads the field.
Kasimdzhanov, playing black, easily split points with the second seed in the first game of the World chess championship final.
The Uzbekistan Grandmaster will meet Michael Adams of England in the final of the World chess championship.
Top seed GM Veselin Topalov of Bulgaria drew his first game against GM Rustam Kasimdzhanov of Uzbekistan in the semi-final of the World Chess championship.
Rustam Kasmidzhanov and Vladimir Akopian also entered the quarter-finals in the World chess championship.\n\n
The top seeded Grandmaster recorded his fifth straight victory in the World chess championship.
IM Neelotpal Das also continued with his good form and held GM Ashot Anastesian for the second time in the World Chess championship.
The Indian Grandmaster played a draw against highly regarded Ukranian in the first game of the second round in the World Chess Championship.\n\n
The Bulgarian GM won the first game of the women's World Chess Championship final against Ekaterina Kovalevskaya of Russia.
India's latest GM is hoping to improve on his third placing at the last World championship in Goa.
Anand has 5.5 points and is tied for third with Alexander Morozevich in the tenth round of the FIDE World Chess championships.
The Indian ace was forced to take a draw in just 17 moves in the ninth round of the World Chess Championships.
Veselin Topalov registered his fifth win in six games to stretch his lead to two points at the World Chess Championships.
Viswanathan Anand held an advantage but could not convert it into a win as he played a draw with Peter Leko in the fifth round of the World Chess Championships.
The Indian ace was held to a draw by Veselin Topalov of Bulgaria in the second round of the World Chess Championship.
The 23-year-old becomes India's 11 Grandmaster.
Joining the Bulgarian in the semi-finals of the World Chess Championship are England's Michael Adams, Teimour Radjabov of Azerbaijan and Rustam Kasimdzhanov of Uzbekistan.
Koneru Humpy crashed through the defence of Xu Yuhua to win the first game of the quarter-finals in the Women's World Chess championship 2004.
The King is wounded but not dead. Defending champion Viswanathan Anand bounced back with a draw against Norwegian Magnus Carlsen.
The British GM pulled off a scintillating victory over Rustam Kasimdzhanov of Uzbekistan to tie the World chess final 2.5-2.5.
GM Michael Adams made it to the finals of the World Chess Championship with a 2.5-1.5 win over GM Teimour Radjabov.
The Indian GM beat Woman Grandmaster Xu Yuhua of China in the second game of the quarter-finals of the Women's World Chess championship.
After beating Tatiana Kosintseva in the first game the Indian ace lost to the Russian in the second in the World women's chass championship.
World No.1 and challenger Magnus Carlsen of Norway beat defending champion Viswanathan Anand in the World Chess Championship 6.5-3.5 after Game 10 ended in a draw at the Hyatt Regency Hotel in Chennai on Friday.
The Uzbekistan Grandmaster beat Michael Adams of England 1.5-0.5 in the tie-breaker to win the title.
Defending champion Magnus Carlsen's hopes of retaining his crown he won last year in Chennai got a boost after the tenth game in the World Chess Championship match against challenger Viswanathan Anand ended in a draw after 32 moves in Sochi on Friday. With two rounds to go in the 12-game match, Carlsen, who played with black pieces, leads 5.5-4.5.
Anand, as white, had simply an extra pawn and this is where the tenacity of Carlsen came to fore.
Former World champion Viswanathan Anand on Tuesday beat Fabiano Caruana of United States in the sixth round to register his first win of the Altibox Norway chess tournament in Stavanger.
Former world champion Viswanathan Anand's bad form continued as he finished 22nd in the World Blitz Chess championship, which concluded in Berlin on Thursday.
Former World champion Viswanathan Anand played out a second straight draw by holding Fabiano Caruana of the United States easily in the fourth round of the Sinquefield Cup, which is part of the Grand Chess tour.
Five-time World Champion Viswanathan Anand set to return to FIDE World Cup after 15 years with an aim to seal a berth at the 2018 Candidates tournament.
Defending champion Viswanathan Anand played out another tame draw as challenger Magnus Carlsen retained his two-point lead after the eighth game of the World Chess Championship.