World champion Nick Matthew kept alive his hopes of a hat-trick of titles and ended Amr Shabana\'s dream of a full hand of five, producing a tactically masterful display in the quarter-finals of the world championships here on Wednesday. The 32-year-old late-blossoming Englishman beat the 33-year-old Egyptian legend 11-5, 9-11, 11-5, 11-4, delivering his increases in pace at cleverly timed moments to cause maximum discomfort to the brilliant four-times former champion. Matthew was also able to attack a surprising amount against one of the most creative stroke-players in the game. Even though Shabana played more positively in the middle of the match, The defending champion ended by winning a sequence of rallies at the front. \"I felt he was a little passive in the first game,\" said Matthew. \"But he was more aggressive in the second. In the third I thought I would hang in and keep it level pegging till about 4-4 and then make a push - and it seemed to work. \"He\'s a class act. He called the pick-ups down when it wasn\'t at all obvious, and it showed that he is a true role model. I felt for him because I know he really wanted a fifth world title.\" Shabana picked up his bags and left hurriedly as soon as the match was over, far too disappointed to join in any public dialogues and post-mortems. Matthew may have an even bigger task in the semi-final however, for he plays the game\'s most sensational player, Ramy Ashour. The fifth-seeded Egyptian won the match of the tournament so far, by 12-10, 10-12, 11-6, 9-11, 11-3 against Greg Gaultier, the former world number one from France. The contest had an edgy, patchy beginning, but changed dramatically from the moment the Australian referee Damien Green told them:\"everyone is here to see the best two squash players in the world - not two blockers!\" Matthew and James Willstrop may not have appreciated Green\'s remark but Ashour and Gaultier evidently did, for thereafter they produced a scintillating contest full of unpredictable shots and startling athleticism which at the end had the crowd standing to applaud. Ashour admitted though that the 92-minute match may well have taken something out of him. \"I hope there\'s something in the tank for tomorrow,\" he said. \"But I hope it takes an age until tomorrow comes. \"I feel full of myself and then I go on court and someone starts slamming it (the ball) around - and suddenly you feel you can lose any time. In life you always have to be on your toes and be cautious or you will be beaten down. \"Hopefully I will have something left in the tank and I can produce some more squash.\" The other semi-final will be between Willstrop, the world number one from England, and Mohammed El Shorbagy, the England-based former world junior champion from Egypt. Willstrop had to abandon his customary fluency and show that he is capable of winning ugly in a 11-7, 11-7, 11-5 victory against the tenacious 15th-seeded Spaniard Borja Golan. Fully 57 refereeing decisions were required to sort out the collisions and disputes. El Shorbagy caused a minor upset by winning 11-9, 12-10, 11-9 against his compatriot Karim Darwish, the former world number one, and will be the only one of the four not to have played a world semi-final before.