A spineless India slumped to their third heaviest Test defeat as Sri Lanka clinched the first Test by an innings and 239 runs with the spin combination of Muttiah Muralitharan and Ajantha Mendis plotting the visitors' downfall in Colombo on Saturday. After enforcing the follow-on, Muralitharan (6 for 26) and Mendis (4 for 60) tore through the Indian batting order to bundle out the visitors for a paltry 138 to record Sri Lanka's biggest victory at home with a day to spare.