Shares of Asian Paints fell nearly 5% on Monday to the day's low of Rs 2,847.80 on the NSE in the opening trade after CLSA downgraded the stock to 'Sell' from an earlier rating of 'Underperform'. In its review of the stock, the Hong Kong-based brokerage maintained that growing competition could have an impact on the near-term growth and margins of the paint maker.