The Sensex tumbled to a low of 14,830 in opening trades. The index has recovered some of its losses and is now down 61 to 14,949.Infosys has slumped 4.5% to Rs 1,929, and TCS has plunged 4% to Rs 1,139. Satyam has shed 3% to Rs 482.Dr.Reddy's and Tata Motors are down 1% each at Rs 673 and Rs 738, respectively.