The Lions squad to tour Australia this summer will not be revealed until after the Heineken Cup semi-finals on April 21.
Lions manager Donal Lenihan has confirmed the delay - April 12 had been an initial target announcement date - as final checks are made on squad candidates.
It gives Irish players, especially, a chance to impress Lions coach Graham Henry.
The foot and mouth epidemic has caused three of Ireland's Six Nations Championship matches - against Wales, England and Scotland - to be postponed.
And with those games looking increasingly unlikely to take place this season - the Six Nations Committee meets again on Sunday for further discussions - Irish players have suffered more than most.
Henry though, will attend a hastily-organised game between Munster and the Rest of Ireland in Limerick on April 13, then travel to Lille for Munster's Heineken Cup semi-final against Stade Francais eight days later.
"The Irish players are back playing some club matches, but you cannot judge them on those games," Lenihan said.
"The Heineken Cup tournament is a higher level than any of the domestic competitions in England, Ireland, Scotland and Wales - it is a far more competitive environment.
"Both semi-finals - Munster versus Stade Francais and Leicester against Gloucester - are huge games, and we have delayed announcing our tour squad until after those matches.
"But, to be fair to everyone involved, we cannot go much beyond the end of April.
"With the disruption we've had to the Six Nations, we would have been in serious trouble if that had been our only criteria for selection," Lenihan added.
"However, the Heineken Cup, along with the autumn internationals, have been major boosts from a Lions selection point of view."
A provisional 67-man Lions squad was announced last month, but the final tour party will comprise 37 players.
The Lions are scheduled to leave London on June 1, kicking off the 10-match, three-Test trip against Western Australia in Perth a week later.