IT was almost uncanny as Irishman Brian Murphy was the first to admit late last Saturday night. It was a routine meeting for the Macau Canidrome, the 14-race weekend programme with a good attendance. In the officials' box, the television set was tuned to the Grand National and the farcical problems besetting England's greatest race. On the track in Macau it was the start of a 745-yard marathon, easily the longest race in the calendar there. At Aintree, it was false start number one and those in the officials' box were keeping one eye on the National and the other on the closed circuit monitors. Suddenly, at the half-way stage of the race, two dogs turned back and started to race towards the field. ''It very, very rarely happens but it did on Saturday. The race was turning into a shambles, rather like Aintree, I'm afraid,'' said Murphy. The trackmanager was left with only one course of action: to declare Race 10 on the Macau Canidrome void. That was done about 12 minutes before Hongkong Stewards declared the Grand National void and 20 minutes before their Liverpool counterparts followed suit. ''I have seen only two races declared void here in five years. And it happened at the same time as the Grand National. Hard to believe,'' added Murphy. It's a big weekend for the Canidrome with the Easter Cup final taking pride of place tomorrow night. Some of the fancied runners took an early fall in the preliminary heats and smart Hacsa Scenery could be the one to beat in the 550-yard showdown. Hacsa Scenery was stepped up to this distance in her heat last week and blitzed the field, winning going away by a length-and-a-half. That was from barrier five so her task will be made easier in the final by a barrier two draw. Biggest danger could be Smarty Jack (5) who clocked 30.7 last week in winning his heat by a runaway five lengths. It's highly unlikely, however, that the winning dog in the Easter Cup will better a landmark record time set recently for the 550-yard distance. For the first time in the 27-year history of the Canidrome, the 30 second barrier was broken, American-bred Splendid Hibiscus clocking 29.9.