O’Neill has been credited with offering McClean, 22, an opportunity in the Sunderland first team following his signature from Derry City last summer when he was brought in by former boss Steve Bruce.
However, O’Neill concedes that a reserve outing convinced him of the youngster’s ability. “I didn’t know him at all,” he said.
“I met him during my first week. He had been substitute for a number of games without ever getting on the field of play, but I did see him play for our reserves against Manchester United during my first week at the club.
“The conditions were terribly windy and the pitch was not great but after a slow start in the game I thought he made a very decent contribution.
“I put him on against Blackburn in effectively my first game in charge of the team in the 75th minute when it looked like we had run out of ideas to break Blackburn down.
“He came on and gave us a boost – Since making his full debut he has never looked back.”
McClean recently made his debut for the Republic of Ireland in a friendly against the Czech Republic and will be hoping he can make the squad for the upcoming European Championships.
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