Sathiyan had to endure a much tougher challenge and was made to sweat before grinding out a 6-11, 11-5, 2-11, 10-12, 12-10, 11-4, 11-8 verdict against Japan's Yuya Oshima.
The match between Sathiyan and Oshima had several Indian expats on the edge of their seats and their support endeared him to put up a spirited fight against the 15th seeded Japanese.
The turnaround for Sathiyan happened when he held on to the fifth game 12-10 after deuce. He had lost the previous game 10-12 which had given the Japanese a comfortable 3-1 lead.
But winning the fifth game gave Sathiyan the necessary confidence as he a struck a nice rhythm and won the last two games to register a thrilling victory.
An immensely pleased Sathiyan attributed his success to his strong forehand top spin attack.
"I am happy I pulled it off, particularly after losing the fifth game," he said.
But his next outing in the round of 16 will be much tougher he will take on Japanese prodigy Tomokazu Harimato.
For Sharath, who did not have a good track record against Niwa, the win looked rather sweet as he had struggled in most of the games.
Yet, Sharath was impressive throughout and his experience came to the fore when he caused one of the biggest upsets in the championships with his strong backhand fetching him good results.
"I have never beaten him before, last year at the Asian Championships in the team event I had three match points and lost. In the first game I was ahead 8-5 and lost, in the second I was down 8-5 and won. The only way for me to beat him was to use my power, take some risks. In rallies I had no chance against him. I also tried to slow down and not play fast," Sharath said after the match.
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