"I knew I had to be careful. The only cure was rest and I had to be patient," said the 33 cap Irishman.
"Maybe I was a little rusty early on, but the more the game went on I felt much better.
"Naturally I'm delighted to receive a late call up but have every sympathy for Manchester City's Richard Dunne, who had to be substituted in that Maine Road game with a calf injury at half-time. We'll see a lot more of big Richard in an Ireland shirt.
"Four years ago I was in the Ireland team that went so close to reaching the World Cup finals in France only to be beaten by Belgium 3-2 in the two-legged play-off.
"Inexperience is no longer a factor. Most of the young Irish lads have won over 20 caps since then and we will be ready for the play-offs irrespective of the opposition."