World number one Lee Chong Wei ended one fairytale and continued another as he reached the men's singles semi-finals at the world championships. Lee's 21-7, 21-13 win over Kevin Cordon kept him on course to become the first Malaysian ever to win a world badminton title, but finished the dream of the man from central America. Cordon was the first player from Guatemala ever to progress so far in a major tournament after three wins, including a giant-killing win over Chen Long, the fifth-seeded Chinese player. But though he managed to strike a few good blows and earned enthusiastic support from the Wembley crowd, Cordon could not match a Lee who has been in the best form of his career. It was followed by an admission from the world's leading player that, depending on the state of his aching body, he might retire after the London 2012 Olympics in the same Wembley arena. "It was difficult to play against him," said Cordon, a 24-year-old who is based in Madrid. "But it gives me a lot of confidence to aim for something even higher." Lee, best known for speedy movement and accurate rallying which applies cumulative pressure to opponents, was once again minded to attempt shorter, more spectacular conclusions to the rallies. Half way through the first game he produced one brilliantly disguised flick from the net which made Cordon turn to retrieve, and combined it with a devastating sliced smash winner. Lee then accelerated dazzlingly from 11-5 to 16-5 during which he appeared to be unstoppable. In the second game he appeared to relax a little but made another thrust from 13-10 to 19-12, during which Cordon did well to stay in some of the rallies. Lee then ended the match spectacularly, diving full length to make a defensive block, getting up and turning to make a retrieve in the back corner and then concluding with a rapier smash. "I think I have been on top form, and it was good that I could win like this because a key to winning the world championships is keeping my energy," said Lee. He had not watched Lin Dan, the three-times former world champion from China who is his main rival, he said, because his way is always to focus on himself and what he needs to do. Lee's likely semi-final opponent is Chen Jin, the sixth-seeded defending world champion from China, whom he beat in three games at the Asian Games in Guangzhou.