Manchester United academy talent Tyler Fletcher called up to Scotland's World Cup squad

The son of former Scotland captain Darren Fletcher, the midfielder was among a group of young players used by Clarke to train alongside the squad over the past week.

The 19 year old was then brought on for his international debut in the second half of Saturday's 4-1 friendly win over Curacao.

Rangers' Connor Barron, Udinese's Lennon Miller and Andy Irving of Sparta Prague were the midfielders originally placed on Clarke's reserve list.

But Fletcher has overtaken them, despite having only played 17 minutes of senior football for United.

"I had to break the news to three other players again this morning, telling them they had missed out," said Clarke.

"I simply felt that Tyler joined the squad this week and performed really well, and did well in the match, so that was the reasoning behind that decision.

"Obviously I am devastated for Billy and also really disappointed for Lennon, Andy Irving and Connor Barron."

Scotland fly out to the United States on Sunday to continue their World Cup preparations.

Clarke's team face Bolivia in a final warm up friendly on June 6.