Lleyton Hewitt booked an Olympic showdown with Novak Djokovic after clinching a surprise 6-4, 7-5 win over Croatian 13th seed Marin Cilic in the second round on Tuesday. After waiting for several hours to start his match due to persistent rain in south-west London, 31-year-old Hewitt ripped into Cilic from the off and never let the big-serving Croat get into his stride. Hewitt's trademark returns of serve proved the key as he secured two vital breaks, one in each set, to seal a victory. Hewitt's world ranking has sunk to 158 after several years of injury problems and the 2002 Wimbledon champion needed a wild card to make it into the Games. But the 31-year-old, who will also play in the mixed doubles with Samantha Stosur, is determined to make the most of what is likely to be his final chance to improve on a miserable Olympic record. Hewitt crashed out in the first round in Sydney in 2000 and lost to eventual gold medal winner Rafael Nadal in the second round in Beijing in 2008.