The Sensex on Monday rose by almost 58 points in opening trade on buying by funds and retail investors. The 30-share index, which surged by over 841 points in the previous three sessions, gathered another 58 points, or 0.34 per cent, to 16,921 points. Auto, metals and oil and gas sector stocks led the gains. The wide-based National Stock Exchange index Nifty also rose by 16 points, or 0.30 per cent, to 5,082 points. Brokers said positive trend in Asian markets and strong corporate earnings, mainly triggered buying by foreign funds on the domestic bourses.