Serena Williams will fight for an 18th Grand Slam title against Caroline Wozniacki in women's singles at the US Open final in New York tomorrow. Serena swept past Ekaterina Makarova 6-1, 6-3 yesterday to reach the US Open final. Serena is already a winner of the past two titles at Flushing Meadows and five overall. In men's singles,Novak Djokovic and Roger Federer stand on the verge of a third showdown at the highest level.Top-seeded Djokovic will face Japan's Kei Nishikori and Federer, the number two seed, will play Marin Cilic of Croatia in today's semi-finals.The top two seeds will be huge favourites to meet again in Monday's final.