Euro 2016: Wales squad as chosen by Danny Gabbidon and Iwan Roberts

Wales players celebrate qualifying for Euro 2016 after beating Andorra in October 2015

Wednesday marks 100 days until the start of 2016 European Championship finals, the first major tournament to include Wales since the 1958 World Cup.

Preparations are under way as Slovakia, England and Russia await in Group B, with a training base chosen in France and friendly matches arranged for March and June.

One of the most important tasks facing manager Chris Coleman between now and Wales' opening game of the competition against Slovakia in Bordeaux on 11 June is to select his 23-man squad.

Former Wales internationals Danny Gabbidon and Iwan Roberts join BBC Wales football correspondent Rob Phillips in choosing their teams for the Slovakia match, their 23-man squads and assess the choices facing Coleman and his coaches.

Wales team v Slovakia - only one difference

Former Wales striker Iwan Roberts: (5-3-2) Hennessey; Gunter, Collins, A. Williams, Davies, Taylor; Ledley, Allen, Ramsey; Bale, Robson-Kanu.

Former Wales defender Danny Gabbidon: (5-3-2) Hennessey; Gunter, Collins, A. Williams, Davies, Taylor; Allen, Ledley, Ramsey; Bale, J Williams.

BBC Wales football correspondent Rob Phillips: (5-3-2) Hennessey; Gunter, Collins, A. Williams, Davies, Taylor; Allen, Ledley, Ramsey; Bale, Robson-Kanu.

Mainstays

Joe Ledley scored in Wales' 3-2 friendly defeat to Netherlands in November 2015

Roberts: "It's so important we have a strong backbone to the team in the likes of Wayne Hennesey, Ashley Williams, Joe Allen, Joe Ledley and Hal Robson-Kanu - the battling and hard work these players produce will give the likes of Aaron Ramsey and Gareth Bale a platform to go and show their class."

Gabbidon: "There are three cogs in the Wales wheel. Captain Ashley Williams marshals the defence, Joe Ledley and Joe Allen give added protection and instigate the attacks, while Gareth Bale and Aaron Ramsey are the match-winners."

Phillips: "Wales have x-factor in Gareth Bale, a player any other side in the finals would welcome. Ashley Williams, Wayne Hennessey and Aaron Ramsey need to be on form, too. Don't underestimate Joe Ledley - a midfielder who does the unheralded ugly stuff."

Maybes

Chris Coleman (left) sprang a surprise by selecting Jazz Richards for the 1-0 win against Belgium in June 2015

Roberts: "I think the likes of Jonny and George Williams, two young and lively creative players, have done enough in the last two years to win a place in the squad. Young full-back Jazz Richards has performed admirably when called upon in four of the qualifiers - including the win over Belgium - and in my opinion should be on the plane to France."

Gabbidon: "George Williams and Wolves midfielder Dave Edwards must be among those who will have to prove themselves after time on the sidelines because of injury."

Phillips: "I tried hard to fit George Williams into the squad as searing pace is a must at international level. Birmingham attacker David Cotterill could still make it as he battles back from injury. Dave Edwards is included, but for reasons of injury may still be a 'maybe'."

Tom Lawrence made his first Wales start in the friendly loss to Netherlands in November 2015

Outsiders

Roberts: "I don't think there will be many, if any, surprises in Chris' squad. I think it's too late for Regan Poole, Manchester United's newest debutant, to break in. The 17-year-old is definitely one for the future but but hasn't done nearly enough up to now to warrant a place in the squad.

"Tom Bradshaw has had a decent season for Walsall but, with the emergence of Tom Lawrence and after his performance against the Netherlands in our last game, Lawrence deserves to go to the Euros."

Gabbidon: "No outsiders can make the squad unless there are injuries. But if Chris Coleman is looking to give someone his 50th cap, I'm available gaffer!"

Regan Poole was released by the Cardiff City academy before joining Newport

Phillips: "It comes down to two for me. Begging the pardon of Walsall fans but, had Tom Bradshaw moved to a higher club in January, he might have clinched a place. A run of goals now might still clinch him a spot as a wildcard substitute if Wales need a goal.

"Regan Poole's entry at Manchester United might have just come too late but I can't help thinking if Chris Coleman wanted to take one for the future - like England's Theo Walcott at the 2006 World Cup - Poole is the one."

Wales' 23-man squad - according to the pundits