At 3:30 on Wednesday the Sensex settled just 17 points from 74000, the most loaded strike on its board, with its own weekly expiry due this morning. A bullseye for the option sellers. Then overnight the table moved. Wall Street's tech selloff ran a second straight day, the Nasdaq fell close to 2 percent, and India's pre market screen slid through the morning to point at an opening gap of roughly 165 Nifty points. Expiry day now opens about 500 points below the magnet, sitting right on the cushion at 73500. The first 30 minutes will decide everything.

Wednesday was two markets wearing one index. Nifty closed 23215, down 27 points, while the Sensex closed 73983, up 64. Underneath, 34 of 50 Nifty stocks fell, the midcap index lost one and a half percent, and media, energy and metal all dropped about 2 percent. The only green was FMCG and the b ...