India's Leander Paes and his Czech partner Radek Stepanek have stormed into the Men's Doubles semi-finals of the ATP World Tour Finals in London. By defeating the Spanish pair of Marcel Granollers and Marc Lopez, 7-5, 6-4 last evening, the third seeded Indo-Czech duo registered its second consecutive Group-A victory, making it to the last four stage. Paes and Stepanek will clash with America's top seeded Bryan brothers – Bob and Mike – in their third and final group match on Saturday.Meanwhile, the fifth seeded Indian duo of Mahesh Bhupathi and Rohan Bopanna will take on the second seeded Belarusian-Canadian combination of Max Mirnyi and Daniel Nestor in a must win Group-B match today. If the Indian pair wins, it will virtually seal a semi-final berth.