"We need to make Goodison a hostile place," the Everton manager said. "Reykjavik are used to playing in front of crowds of one or two thousand but it will be different this time. We need to unsettle them as soon as possible, and the fans can play their part. "
Royle's appeal indicates that he is not taking Everton's passage to the second round for granted against a side which has already qualified for Europe next year by winning their domestic cup again.
Everton will be without their captain, Dave Watson, who has a stomach muscle strain, though David Unsworth, who scored from the penalty spot in Iceland, will return after being dropped and then suspended.
The Welsh captain, Barry Horne, again falls victim to the restrictions on foreign players, with Anders Limpar recalled to a starting line-up Royle described recently as "toothless".
Celtic, who entertain Dynamo Batumi tonight in their Cup-Winners' game, are waiting on fitness tests for Pierre van Hooijdonk, Andreas Thom and Phil O'Donnell as they prepare to defend a 3-2 first leg that was described yesterday by the Georgians' manager, Valerian Chkhartishvili, as "an accident". The unsettled midfielder John Collins, dropped for the weekend victory at Hearts after his comments in a television interview, is back in the squad.