The Silk Cut Challenge Cup finalists put out a side with no regular first-team player and lost 58-0.
A sub-committee of the Rugby League's board of directors yesterday imposed the fine after hearing an explanation of players' unavailability from Leeds' coach, Doug Laughton. 'The committee noted that 11 players had recovered sufficiently to face Leigh this Sunday,' the League's spokesman, Harry Gration, said.
The fine, while heavy by rugby league standards, pales by comparison with the pounds 38,000 prize for the winners at Wembley and the much higher spin-off earnings available to finalists.
'We are disappointed, because we had medical certificates to cover nine players,' Leeds' chief executive, Alf Davies, said. 'But we will not be appealing against the fine.'
Meanwhile, St Helens have warned that they will be forced by injuries to field a below-strength side in the vital championship match at Bradford tonight.
Bradford's chairman, Chris Caisley, has resigned from the League's board of directors, amid the controversy over the instruction that his club must play its potentially title-deciding final league match of the season at Leeds on Saturday afternoon.
The League yesterday shrugged off Bradford's protest at the changed schedule, which sees Warrington play their last match on Friday night and Wigan play theirs on Sunday night.
Va'aiga Tuigamala is set to be preferred to Jason Robinson on Wigan's right wing against Castleford tomorrow, even though Robinson is now fit after a foot injury.
'Inga did well enough against Bradford last week to hold his place,' the Wigan coach, John Dorahy, said.
The draw for next year's Centenary World Cup is to be held in Brisbane on 2 June, the day after the World Club Challenge between the Brisbane Broncos and the British champions.Reuse content