Farhan, a former world youth champion, took victory in straight sets (21–12, 21–9) to progress to the third round - the last 16 stage of the men's singles competition.
Having come through a tense three-set match with Vietnam's Le Duc Phat in the first round, a tie with the 11th seed was going to be a tall order for the 23-year-old Finn ranked 48th in the world.
1-1 in the opening set was the last time the two opponents were level, as Farhan gradually built his lead. In the second, Oldorff's hopes were over before they had begun, as he lost the opening 10 points to give himself a mountain to climb, as Farhan cruised to a comfortable victory.
In doing so, the 21-year-old Indonesian has ended Finnish interest in the 2026 world championship, after their only other representative in India, Kalle Koljonen, was knocked out in the opening round by Panitchaphon Teeraratsakul of Thailand.
The Finn pushed hard in the opening set, going down 21-18, but didn't have enough left in the tank in the second set, falling to a 21-9 loss.
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