The bellwether index swung between a high of 6,725.15 and a low of 6,650.40, before settling at 6,695.05, showing a mere gain of 0.70 point or 0.01 per cent on the National Stock Exchange (NSE).
Auto, metal and FMCG-related stocks witnessed good buying interest, while healthcare, technology and realty succumbed to profit-taking.
After a flat opening, the key indices gained momentum and crept higher to reclaim the key psychological 6,700 mark after recent sell-off, but soon encountered selling at higher levels and slipped into red. It remained under intense pressure throughout the session before rebounding smartly in tail-end buying spree.
Meanwhile in corporate action, both Sun Pharmaceutical Industries and Ranbaxy stocks were in focus today following the acquisition news.
Sun Pharma will acquire Ranbaxy Laboratories, which has been facing quality issues for its drugs in the US market, in an all-stock transaction with a total equity value of USD 3.2 billion.
With the start of 36-day long Lok Sabha voting process, the market is likely to see extreme volatility and caution among investors, traders commented.
Elsewhere in Asia, markets mostly suffered a sell-off with Japan's benchmark index Nikkei and Hong Kong Hang Seng index dropping sharply to hit multi-week lows following last weekend's heavy profit-taking session in Wall Street led by technology sector stocks.
Ultracemco, Ambuja Cement, Sunpharma, NMDC, Sesa Sterlite, Asian Paint, Kotak, M&M, Tata Steel and Coal India were the top index stock gainers.
Key losers included Jindal Steel, BHEL, DLF, IDFC, Cipla, ICICI Bank, Lupin, Dr Reddy, BPCL and Infosys.
Turnover in the cash segment dropped to Rs 13,450.74 crore from Rs 14,302.63 crore last Friday. A total of 9,037.81 lakh shares changed hands in 62,20,550 trades, while market capitalisation stood at Rs 73,10,111 crore.