The Indian equity benchmarks gained for third session in a row on Wednesday paced by gains in financial and banking shares a day ahead of monthly expiry of futures and option contracts. The benchmarks staged a gap up opening and extended gains during the session taking cues from strong global markets as hopes of a negotiated end to the Ukraine conflict spurred buying interest for equities. The Sensex rose as much as 784 points at the day's highest level and Nifty 50 index touched an intraday high of 17,522.