After the early struggle in the tournament when he was stretched to five games by an Egyptian Mazen Gamal, a qualifier in the first round, the fourth seeded Indian was in his elements against Hong Kong's Tsz Fung Yip.
Against the Egyptian, Ghosal had to come back from two games down to stage a dramatic return.
The 85 minute tussle ended 5-11, 8-11, 11-2, 11-3, 11-6 in Ghosal's favour.
Against the Hong Kong player, the Indian carved out a 11 -7, 11-5, 11-6 win in 38 minutes. Ghosal is to play the top seed German, Simon Rosner, in the semifinals tomorrow.
Sandhu lost to Egyptian Omar Mosaad, the fifth seed but after giving a fight. The Egyptian won 11-1, 8-11, 11-9, 7-11, 11-2 in 65 minutes.