Zagreb (Croatia): Former world champion Viswanathan Anand suffered a shock defeat against Ian Nepomniachtchi of Russia in the first round of the Croatia Grand Chess tour, here.
It turned out to be a bad day in office for Anand, who played with whites, as despite getting a promising position he could not make much of it and it pretty much slipped out of hand in no time.
Starting with the in-vogue Italian opening Anand was pleasantly surprised by Nepomniachtchi's slightly passive opening choice and cashed in on the opportunity early to launch a king side attack.
The Russian was feeling the heat early on and his bid for counter-play on the queen side did not meet the right moves.
After the Queens got traded, Nepomniachtchi was on top and converted his superior position into a full point after 32 moves.
The story of the day was world champion Magnus Carlsen's 23-move triumph over Anish Giri of Holland. Playing the black side of a Sicilian Rossolimo, Carlsen came up with a dubious eighth move leaving his own pawn structure shattered.
It was not so easy to play over the board and Giri simply collapsed when Carlsen launched a king side offensive.
"It was really a case of just playing the man instead of the position," said Carlsen after the game about his dubious opening choice.
"I thought that it was such a stupid move that he wouldn't have looked at it, and I felt that the resulting positions were just completely unclear. It was not at all obvious that they were bad for me, so I thought that would be a very good thing for me, just to get him out of book and to get an unclear position from the get-go, he added.
Fabiano Caruana of United States came up with a fine new idea in the Queen's gambit declined to beat compatriot Hikaru Nakamura while another American, Wesley So, defeated Ding Liren of China on what was a highly entertaining first day in the tournament.
Shakhriyar Mamedyarov of Azerbaijan and Sergey Karjakin of Russia played out an interesting draw and the other game of the 12-player round-robin event also ended peacefully between Maxime Vachier-Lagrave of France and Levon Aronian of Armenia.
With four decisive games in the opener, Carlsen, Caruana, Wesley and Nepomniachtchi have emerged as the early leaders in the USD 325000 prize money event that has 90000 USD as the first prize.
Results round 1: Viswanathan Anand (Ind) lost to Ian Nepomniachtchi (Rus); Anish Giri (Ned) lost to Magnus Carlsen (Nor); Shakhriyar Mamedyarov (Aze) drew with Sergey Karjakin (Rus); Maxime Vachier-Lagrave (Fra) drew with Levon Aronian (Arm); Wesley So (Usa) beat Ding Liren (Chn); Fabiano Caruana (Usa) beat Hikaru Nakamura (Usa).