CINCINNATI — Rafa Nadal continued his sizzling hardcourt form beating John Isner 7-6 (10-8), 7-6 (7-3) in the final of the Western and Southern Open Sunday, setting up the Spaniard as the red-hot favorite heading into the US Open. Unbeaten on the surface this year and coming off a win in Montreal, the third ranked Nadal ran his record on the pavement to 15-0 winning back-to-back hardcourt finals on consecutive weeks for the first time in his career. Nadal needed nearly two hours on a muggy center court to tame the towering in-form American, who had knocked off three top 10 players, including world No. 1 Novak Djokovic, to earn his spot in the final. But the big-hitting Isner had no answers for the relentless Nadal, who has now claimed nine titles from 12 events this season. It was the 59th win of Nadal's career but first in nine tries on the Cincinnati hardcourts. Nadal had rolled over sixth seed Tomas Berdych 7-5, 7-6 (7-4) Saturday to set up the final with Isner. Isner benefitted as Juan Martin del Potro double-faulted on match point to open the door to the unseeded American, who took full advantage by rallying for a 6-7 (5-7), 7-6 (11-9), 6-3 victory. On the women's side Saturday, Serena Williams staged comebacks in both sets to defeat China's Li Na 7-5, 7-5 and reach the final at the Cincinnati WTA tournament for the first time. She will face off for the title against world No. 2 Victoria Azarenka, who won a match plagued by breaks of serve — 23 in total, including the first six games — to defeat 2011 finalist Jelena Jankovic 4-6, 6-2, 6-3. Azarenka and Williams will both be playing for their first title at the tournament. Azarenka finally earned her victory with a concluding break of former No. 1 Jankovic. Serena, who has won 15 titles in the last 16 months and is bidding for her ninth this season, needed just over 90 minutes to advance against the error-prone 2012 winner here. — Agencies