Wales boss John Toshack fears his World Cup plans will be wrecked by the long-term injury absences of four of his top stars.
And he has now virtually put a May deadline on knowing whether he will have his key men for the opening qualifiers for South Africa 2010, with crunch games against Russia and Germany at the beginning of next term.
Toshack will send out an experimental side here on Wednesday in the Stade Josy Barthel for a friendly that will give him the chance to run the rule over a host of fringe players from the lower divisions.
But it his three West Ham players - Craig Bellamy, Danny Gabbidon and James Collins - plus youngster Gareth Bale at Tottenham, who are giving him serious concerns.
And Toshack reveals that before he names his squad for two friendlies in May against Iceland and Holland, he aims to have held crunch talks with their respective club managers over their fitness prospects.
Collins is not expected back until October after a cruciate knee operation, Bellamy is still fighting for fitness after yet another groin operation, while Gabbidon is still suffering from a long-term groin problem.
Bale has a long-term ankle injury that has ruined the beginning of his Spurs career after his big-money move from Cardiff.
The quartet are vital to Toshack, and he is growing increasingly concerned about whether he will see any of them for the big games coming up.
Toshack said: "We are very concerned about the Collins-Gabbidon injury situation in central defence. While our top striker Bellamy has also been out for a very long time.
"We have spent three years working on a defensive plan and it is worrying and disappointing that we are without them and they have the problems they have.
"There seems no real sign of Gabbidon coming back at all, Collins we know will be out until at least September with his cruciate knee injury.
"The centre-back situation has become an area where we need to be concerned. We have thrown in Craig Morgan, but it is a big step up from where he is playing (at Peterborough) to face the likes of Russia and Germany in the qualifiers next season.
"We also have Gareth Bale out long term, it's five months since he last played for us.
"Any international team would miss four players of that quality, but for us it really is a major blow."
Hull goalkeeper Boaz Myhill and Stockport defender Ashley Williams are expected to make their Wales debuts here.
That will make it 28 players that Toshack has capped in his 31 matches as Wales boss.
He added: "With those four and the likes of Simon Davies, Jason Koumas and Carl Fletcher, plus the young players we have got coming through now from the under-21s, we feel we are a lot stronger.
"But the clock is ticking now. We start our World Cup qualifiers in September, and with us at full strength I do feel we are much better and have a chance.
"The under-21s are the best squad this country has ever had, in my view, but we must have the experienced lads around them.
"But without the four injured players we have a genuine concern now. I need to know as soon as possible when these players are going to be ready.
"So that at least I can plan. We have two games in May in Iceland and Holland, and then our final warm-up game against Georgia in August.
"Then it is straight into the World Cup qualifiers in September and October, with key games against Russia and Germany straight away.
"Within reason I would like to know as soon as possible whether we are going to have these players available or not."
Toshack continued: "I don't want to plan for them being available and then find they won't make it.
"I'd rather think, okay, they are out. If they do make it, that's a bonus, but we have to start looking for alternatives.
"But there are key areas of the team that concern me. Three big Premier League players at West Ham, and Bale at Spurs. They will be huge misses for us if they don't make it.
"Between now and the games in May I intend to see the people concerned. I am to go up to West Ham to see the three lads there, maybe have a talk with their manager.
"I need to know how long I will be without them, and the vibes from West Ham are not good."
Provisional team: Myhill (Hull), Eardley (Oldham), Nyatanga (Barnsley), A Williams (Stockport), Morgan (Peterborough), Ricketts (Hull), Fletcher (Crystal Palace), Koumas (Wigan), S Davies (Fulham), Eastwood (Wolves), Easter (Plymouth).
Substitutes: Price (Derby), Duffy (Portsmouth), S Roberts (Doncaster), Stock (Doncaster), Tudor Jones (Swansea), Cotterill (Sheff Utd), Nardiello (Barnsley).
