Flynn - has named his Under-21 squad.
As Wales try to qualify for their first major finals in 50 years, their under-21s will find themselves considered more important than John Toshack's senior squad later this month.
Not since John Charles and co reached the World Cup finals in Sweden back in 1958 has any Wales side reached a finals.
But if Brian Flynn's youngsters beat Romania at Wrexham on August 20, then they will be one play-off tie away from the UEFA Under-21 Championship in Sweden next summer.
Toshack has a friendly with Georgia at Swansea the same night, the seniors' last warm-up game before they embark on their World Cup qualifiers with Azerbaijan and Russia in September.
But Wales believe they have their best under-21 squad ever, and they will never have a better chance of reaching a finals than now.
So Toshack has given under-21 boss Flynn the right to choose who he wants to face the Romanians.
Flynn selected a 28-man squad today for their final home group match, knowing one victory will win their group and secure a play-off slot in October.
Wales have one further qualifier left, away to Romania on September 9, but Flynn wants to settle the issue at Wrexham.
So he will have the likes of Arsenal new boy Aaron Ramsey, seniors goalkeeper Wayne Hennessey of Wolves, Cardiff midfielder Joe Ledley, Tottenham duo Gareth Bale and Chris Gunter, plus Manchester City's young striker Ched Evans - who has scored nine goals in the last nine under-21 games - at his disposal.
In all, Flynn has been able to name 12 full internationals in his squad, and will also have first call on Lewin Nyatanga and Neal Eardley, both senior squad regulars these days.
On Friday, Toshack will announce his senior squad for the Georgia game, and it will include fit-again Craig Bellamy and Cardiff's FA Cup star Paul Parry, who has finally decided his personal problems allow him back into the Wales fold for the first time in over a year.
Toshack will utilise the players that Flynn does not need, plus the fringe players like Andrew Crofts and Owain Tudur-Jones who are due a run-out.
Robert Earnshaw is also expected to be recalled following the move to Nottingham Forest that ended his Derby misery.
But it will be the young brigade in the spotlight.
Flynn said: "This really is the big one and we need all the support from the Welsh fans possible at the Racecourse on the night.
"We know what we have to do. I, and other members of my staff, have all seen Romania play and we certainly do not underestimate them.
"However, we have done so much hard work over the last year, that we really must look to win the group at home and book our place in the October play-offs."
He added: "We have selected a large squad so that I have the flexibility to look at certain positions now over the next couple of weeks.
"When we get closer to the game, some of the players will be released and that could involve some of the players then reverting to John's squad for the friendly with Georgia.
"John and I have spoken at length regarding the games and he is happy for me to have whoever I think I need for the Romania match. It would be such a huge boost for Welsh football for us to take that next step towards qualifying for a major finals."