Mahajan, from Punjab who had made it to the quarterfinals of the Li Ning Bahrain challenge last month, shut out his more fancied rival 21-17 13-21 21-19 in 55 minutes at the Cricket Club of India to earn a meeting with fourth seed R M V Gurusaidutt for a place in the final.
The other semi-final would be fought by top seed H S Prannoy and sixth seed Ajay Jayaram. The former prevailed in three games against eighth seed Subhankar Dey in just over an hour, while the latter ousted third seed B Sai Praneeth in straight games in a 37-minute quarter-final encounter.
The other semi-final would be between top seed P C Thulasi and former national champion Arundhati Pantawane, seeded fourth.
Women's doubles top seeds Pradnya Gadre and N Sikki Reddy were upset 21-16 24-22 by Aparna Balan and Prajakta Sawant in the quarter-finals.
More From This Section
The results:
Men's singles (Quarter-finals): 1-H S Prannoy beat 8-Subhankar Dey 21-16 19-21 21-13; 6-Ajay Jayaram beat 3-B Sai Praneeth 21-19 21-15; 4-R M V Gurusaidutt w/o 7-Chetan Anand; Akshit Mahajan beat 2-Sourabh Varma 21-17 13-21 21-19.
Women's doubles (Quarter-finals): Aparna Balan/ Prajakta Sawant beat 1-Pradnya Gadre/N Sikki Reddy 21-16 24-22; Shruti Mandala/Rhea Pillai beat Daksha Gautam/Rachita Sahdev 21-10 21-10; J Meghna/K Manisha beat Varsha V Belawadi/ G M Nishchita 21-7 21-15.