Lee Rogers, Centre of Excellence coach at Brighton & Hove Albion and the man who first spotted Barry's ability, told the Sunday Mercury: "Playing for England means something to him because he thought his chance had gone.
"This is where Martin O'Neill comes in. What he has done at Villa is make his players believe they can play for England.
"I know Martin has instilled so much confidence back into Gareth.
"He would have left Villa had it not been for their manager. Spurs would have been his preferred choice but Portsmouth was also a possibility.
"But Martin got him to stay, built his squad around him and then got him back into the England squad at the age of 26.
"It's amazing to see what has happened to Gareth."