Hong Kong will return to group two in Davis Cup action next year after they defeated Sri Lanka 3-0 to remain unbeaten in the Asia/Oceania zone group three promotion-relegation tie at Victoria Park yesterday. With only one match remaining, against Vietnam today, Hong Kong have already booked one of the two promotion slots available in this eight-nation tournament by first topping their preliminary round, and then cementing their position by defeating an up-and-coming Sri Lankan outfit in the second stage of competition. Wayne Wong and Yu Hiu-tung both scored straight-sets victories, each winning by identical scorelines of 7-5, 6-2 against Harshana Godamanne and Renouk Wijemanne respectively. The SAR's doubles pair of Brian Hung and Martin Sayer then wrapped up victory, defeating Godamanne and Rajeev Rajapakse 7-5, 6-1. 'It is good to wrap this up today itself and book our place back in group two,' said a happy Derek Ling, Hong Kong's non-playing captain. But both Wong and Yu took the tough route to victory, making life harder for themselves by losing the plot momentarily when they had the upper hand in the first set. Lapses in concentration - the body language of both Wong and Yu spoke volumes - saw the pair squander chances to finish off their opponents quickly and ruthlessly. Wong was the bigger culprit, leading 5-2 in the first set and up by two breaks of serve, he lost the momentum with his game unravelling while serving for the first set. Left-handed opponent Godamanne took his chances well and saved one set point at 5-3, 40-30, before breaking Wong. The Sri Lankan did it again in the 10th game to level the score at 5-5, but Wong suddenly came to life to break back before holding serve to win the first set. 'It was lucky that his opponent slipped up after breaking back twice. If it had gone into a tie-break anything could have happened. I was just happy that Wayne managed to hold on and I'm just glad that we won,' said Ling. It was a similar case for Yu against Sri Lanka's Wijemanne. An early break of serve gave Yu the upper hand and he led all the way to be serving for the set at 5-4. But when it really mattered, Yu stuttered. A couple of poor points, including one badly judged advance to the net, saw Yu contrive to lose his serve. However, the talented left-hander made amends immediately by breaking Wijemanne in the next game to take a 6-5 lead. And this time he served out safely to clinch the first set. 'They both lack a bit of mental toughness, especially Wayne. This is one part of their game they will have to work on,' admitted Ling. 'But at the same time, they both played the second sets very well.' Yesterday, Hong Kong were fortunate their opponents - who last year were in group four - were unable to make the most of their mental lapses. They won't get any favours next year in group two.