Grandmaster and former world junior champion Pentala Harikrishna survived anxious moments before defeating Yuri Vidal Gonzales of Cuba 3.5-2.5 after two sets of tie-break games to enter the second round of the World Chess Cup.
B Adhiban was the other Indian to move to the round of 64 as he crashed through the defences of Nguyen Ngoc Troung Son of Vietnam also in the rapid games.
However, the third Indian Murali Karthikeyan crashed out after losing the rapid set of tie-break against Francisco Vallejo Pons of Spain.
Former world champion Viswanathan Anand, S P Sethuraman and Vidit Gujarathi had already made it to the second round with victories under normal game itself.
Out of the seven Indians in the fray, as many as five have advanced to the second round now.
It was a day of nerves for Harikrishna as he almost came back from the jaws of defeat in the first set of rapid tie- breaker with 25 minutes and 10 seconds addition after every move.
From a level looking middle game with white pieces, Harikrishna kept looking for some complexities and found himself in a tough situation when the endgame arose in the second game of the rapid.
A loss would mean an ouster but a never-say-die Harikrishna was at the top of his game in difficulties. The Indian pounced on a super trick and found a study-like draw in the end.
Gonzales was apparently hurt deep by this close call and caved in the 10-minute rapid tie-break that followed after the first.
Like Harikrishna, Adhiban also took four more games but did not quite face any serious threat for his bid to enter the second round.
Troung Son, the second highest ranked player in Vietnam, lost tamely with white in the 10-minute game.
Interesting challenges lie ahead for all five Indians in the second round except Anand who will start as an overwhelming favourite against Anton Kovalyev of Canada.
Harikrishna and Sethuraman clash against each other, Vidit Gujrathi plays top Vietnamese Le Quang Liem while Adhiban has a tough customer in Ian Nepomniachtchi of Russia.
Each round in the World Cup consists of two classical games except the final that has four games. Each player plays one game with white and one with black in normal time control and in case of a tied result, rapid, blitz and a final Armageddon games is played to determine the winner.
The total prize fund is USD 1.6 million with the first prize of USD 120,000. Besides, the top two finishers will qualify for the 2018 Candidates' Tournament.