In late night matches, 13th seed Prannoy beat Germany's Lars Schaenzler 21-16 21-13 in a little over half an hour match to set up a meeting with 2010 Commonwealth Games silver medallist Rajiv Ouseph of England, seeded sixth.
Young Sameer also continued to punch above his weight, notching up a stunning 21-19 22-20 win over fourth seed Chinese Wang Zhengming. He will next take on Thailand's Tanongsak Saensomboonsuk, seeded 16th.
B Sai Praneeth also made it to the pre-quarterfinals after prevailing over Uzbekistan's Artyom Savatyugin 21-7 21-10. He will next take on second seed Chou Tien Chen of Chinese Taipei.
Two-time champion and top seed Saina Nehwal and P V Sindhu also reached the pre-quarterfinals of the women's singles competition.
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Olympic bronze medallist Saina saw off Germany's Karin Schnaase 21-7 21-15 in 33 minutes to set up a meeting with Czech's Kristina Gavnholt at St Jakobshalle here.
dished out a gruelling performance to edge out world number 14 Hu Yun 23-21 23-21 in a 47-minute contest.
However, the euphoria was shortlived as Satwiksairaj and Chirag went down 10-21 11-21 to Tsz Kit Chan and Cheuk Him Law in the fourth rubber.
Senior Nationals runners-up, Sourabh, who is making a comeback after a series of injuries, played out of his skin to upset world number 17 Nan Wei 17-21 21-19 21-9 in the third singles.
Indian men, who have qualified for the Thomas Cup Final only eighth times since its inception in 1948-49, will next take on Indonesia in a Group B match tomorrow.