Pandole, ranked 17th in the country, made full use of the home conditions to shock Nikshep in straight sets 6-4 6-4 at the Maharashtra State Lawn Tennis Association's courts.
He set up a quarter-final meeting with 8th seed Nitin Kumar Sinha of West Bengal who prevailed over his state mate Ishaque Eqbal 6-4 7-6(1).
Chandigarh's Param Pun knocked out third seed Sanil Jagtiani of West Bengal, winning 6-3 5-7 6-3, while Maharashtra's Siddhant Banthia stunned Assam's 5th seed Parikshit Somani 6-4 6-1.
Mahesh Mohapatra of Orissa, the top seed in the boys under-12 category, also bowed out after losing to Gujarat's Krish Patel in a long drawn third round encounter at 6-1 2-6 6-1.
Results (Round 3): Girls u-16 singles: 1-Abinikka R (TN) bt Vaidehi Chaudhari (GJ) 6-1 6-1; Sarah Dev (PB) bt Priyana Kalita (AS) 7-6(4) 6-1; 4-Himani Mor (HR) bt Akanksha Bhan (GJ) 6-3 6-3; Rishika Ravi (TN) bt Prinkle Singh (JK) 4-6 6-3 6-3; 7-Jennifer Luikham (HR) bt R Sai Avanthika (TN) 7-5 6-0; 3-Mihika Yadav (MH) bt Shivani Swarup Ingle (MH) 6-2 6-2; 8-Sathwika Sama (AP) bt Baani Singh (PB) 6-2 6-2; Mahak Jain (MH) bt Sabhyata Nihalani (DL) 6-3 6-3.