World No.10 Harika, seeded 36th in this tournament, couldn't keep up with the fourth-seeded Adams and threw in the towel when the game started slipping out of her fingers here late on Monday night.
She has played three games so far, extracting a win and a draw in her first two rounds.
Harika accepted the loss gracefully, pointing out that Adams is a top flight player. "He is a big gun. I started off with some decent moves but Adams countered me well and outplayed me slowly," she conceded.
The Indian GM will next play Germany's Thomas Paehtz, who comes in with a draw against India's GM Aravindh Chithambaram in the earlier round.
