New Delhi, Dec 22 (IANS): Defending champions Parupalli Kashyap and Sayali Gokhale advanced to the semi-finals of the 78th Senior National Badminton Championships in their categories at the Siri Fort Sports Complex here Sunday.

In women's singles, World Championship bronze medallist P.V. Sindhu and Arundhati Pantawane also progressed to the last four. Junior national champion Rituparna Das caused an upset by defeating Mumbai's fourth seed Tanvi Lad.

It was the end of the road for World No.24 and third seed Ajay Jayaram in the men's singles, who was upset by sixth seed B. Sai Praneeth while second seed R.M.V. Gurusaidutt and Thailand Open Grand Prix Gold winner Kidambi Srikanth continued their march to the last four.

In the semi-finals to be played later in the day, seventh seed Sayali will face 15th seed Rituparna while Nagpur's third seed Arundhati will take on last year's runner-up Sindhu.

In the men's singles last four clash, top seed Kashyap will face tough competition from fifth seed Srikanth while Sai will take on Gurusaidutt.

The finals will be played Monday.