Wayne Rooney's possible inclusion will intrigue many as England face Scotland for the first time in almost 14 years at Wembley on Wednesday.
The fixture is the oldest in the history of international football and will be used by manager Roy Hodgson to evaluate his options ahead of crucial FIFA World Cup qualifiers in September.
England will be expected to beat Moldova at Wembley on September 6, but face a testing trip to Ukraine four days later, which will go a long way to deciding who qualifies from UEFA Group H.
Wayne Rooney’s inclusion in the hosts' squad has caused controversy, with the Manchester United man having featured for just 45 minutes of his club's pre-season campaign.
The 27-year-old was sent home from United's tour of Asia due to a hamstring injury, and then suffered a knock to his shoulder in his first appearance – in a behind-closed-doors outing against Real Betis.
However, Hodgson has insisted that Rooney is fit to play, hitting back at claims from Old Trafford boss David Moyes that featuring in the game would only serve to show how unfit the striker is.
If Rooney proves to be ultimately unfit, he may replaced by the squad's debutant – Southampton striker Rickie Lambert.
The 31-year-old netted 15 times in his maiden Premier League season last term, bettered by not one of his countrymen in the top flight and equalled only by Frank Lamaprd.
Whoever England opt to go with, they will not have an easy run against Scotland, who have looked promising under new manager Gordon Strachan, who took the reins in January.
Scotland have won two of the former midfielder's four games in charge, including a superb 1-0 win in their last outing away to Croatia.
The defeat represented just the second time that Croatia had lost a competitive match on home soil – the only other side to have matched Scotland's feat is England.
Strachan could hand international bows to Brighton and Hove Albion defender Gordon Greer and Dundee United attacker Gary Mackay-Steven.
But Scotland are still without the key trio of Darren Fletcher, Gary Caldwell and Steven Fletcher, who remained sidelined through illness and injury.