The PLA's National Day performance helped cause severe pitch damage that will take weeks to fix, Hong Kong Stadium chiefs said yesterday. The chairman of the stadium's board of governors, Ambrose Cheung Wing-sum, said the festivities last Friday had ripped up the turf, and bringing it back to top condition would cost up to $40,000. But he said the damage - ranging from severe in the centre of the pitch to minor at the edges - was less serious than they had expected. 'We're actually very happy,' Mr Cheung said. 'The event was the first of its kind ever held at Hong Kong Stadium and the pitch passed the test with flying colours.' The pitch would be back to normal within three weeks, in time for a soccer match tentatively booked for the end of the month. Mr Cheung and stadium manager Donald Choy Chai-mun said the severity of the damage in the pitch centre - where patches of the surface are bare - did not mean the turf was not up to scratch. 'We're talking about 6,000 people trampling on the pitch - there's going to be some damage,' he said. The Home Affairs Bureau, which organised the National Day performances at the stadium, has paid for 500 square metres of new turf 'tiles' to patch up the pitch. But Mr Choy said it might not be necessary to use all the tiles, worth close to $40,000. The poor state of the pitch was a key factor in former stadium managers Wembley International being superseded by the Urban Council in May last year.