MUMBAI, Nov. 13 -- Indian equities extended their winning streak to a third consecutive week, supported by stronger corporate earnings and sustained foreign buying. But the rally lost momentum, with rising inflation and continued domestic institutional selling raising questions about its durability.

The Nifty fell 0.6% on Friday to close at 25,144.30, while the Sensex declined 0.4% to 81,592.44. For the week, however, the indices gained 0.45% and 0.69%, respectively, following a nearly 9% surge in the previous week.

Improving earnings offered support, with capital goods, financial services and realty stocks leading sectoral gains. But persistent domestic institutional selling and uncertainty over interest rates suggest the market faces ...