Northern Ireland have lost influential defender Jonny Evans for the World Cup qualifier against Azerbaijan on Wednesday, with Andy Little and Alex Bruce also ruled out through injury.
While Little (foot) and Bruce (knee) would be unlikely to make the starting XI for the Group F clash, Evans (groin) is one of Michael O'Neill's most important players and was one of the top performers in the side's memorable 1-1 draw in Portugal last month.
O'Neill has responded to the withdrawals by adding uncapped Liverpool teenager Ryan McLaughlin and Burnley's Danny Lafferty to his squad.
Evans had a modest turnout record in the latter stages of Nigel Worthington's reign but has been a regular since O'Neill took over at the turn of the year, even playing despite carrying a knock against Luxembourg in September.
His withdrawal is mitigated somewhat by the presence of West Brom's Gareth McAuley in the squad.
McAuley was suspended for the Portugal match but should now slot back into the centre of defence, where Craig Cathcart and Aaron Hughes are also available.
Little made a fine start to the season with Rangers, but he has now pulled out of successive Northern Ireland squads due to fitness issues.
Bruce, pencilled in to offer cover at right-back, has also dropped out of the last two parties.
McLaughlin, a highly-rated 18-year-old who has yet to make his senior Liverpool debut, will now deputise at right-back having been promoted from the Under-21 side to face England on Tuesday.
Left-back Lafferty is not a like-for-like replacement for any of the injured players but with Cathcart now needed in the centre, he will vie with Ryan McGivern for a starting spot.
Derby striker Jamie Ward (hamstring) was the first player to be withdrawn from O'Neill's 24-man panel and was yesterday replaced by Inverness' Billy McKay.