Mumbai, Oct 9 (PTI) Wide fluctuations prevailed in the stock market today before key indices Sensex and Nifty closed with measly gains, with institutional investors lending all- crucial support.

The GST Council last week offered relief to exporters and small and medium businesses. Caution prevailed as earnings season for the September quarter kicks off this week, traders said.

The 30-share Sensex rallied to the day's high of 31,935.63, but slipped before ending up 32.67 points -- or 0.10 per cent -- at 31,846.89. Much of the selling was an outcome of a rush to book profit. The gauge had gained 222 points on Friday.

The NSE 50-share after reclaiming the crucial 10,000- mark slipped back to close up 9.05 points, or 0.09 per cent, at 9,988.75. Intra-day, also touched a low of 9,959.45.

GST relief measures prompt modest equity gains amid market volatility as investors weigh earnings season risks. The GST Council announced relief measures for exporters and small and medium enterprises, which influenced market sentiment; equity indices showed modest gains supported by institutional investors amid intraday volatility and profit-booking pressure, with additional caution due to the onset of the September quarter earnings season.