The world no. 22 Indian, playing with white pieces, attacked from the onset and found himself in a winning position but a slight miscalculation saw him surrender the advantage to the second seeded Azerbaijan player.
"I was playing a good game and got into a winning position but played the wrong move to give away the win," Harikrishna said.
"Instead of playing Kh2 on the 28th move, the precise move to win would have been Nc5," he added.
The 31-year-old from Guntur will take on another Azerbaijani Grandmaster and table topper Teimour Radjabov in his fourth round encounter later tonight.
"Teimour has been playing really well in this tournament so far. He is a solid player and I will look to play my normal game and see how it goes," Harikrishna said ahead of the clash.