Former Sunderland chairman Niall Quinn feels Roy Keane is limited in his role as Republic of Ireland assistant manager.
Keane is splitting his duties between Ireland and Aston Villa.
Quinn, who hired Keane as Sunderland manager, said: "It must have been tough for Roy to agree to become an assistant manager, but he was keen to get back into the game at the time and now he also has the job at Villa, which gets him back into the Premier League.
"Fair play to him for agreeing to put his own managerial ambitions on hold for a period and taking up these lesser roles, because they are a step back. However, I'm sure he is looking at this as a period where he can learn and return as a better manager in a few years.
"Roy has plenty to contribute to the Ireland set-up and the players will enjoy being around him. Having experienced first-hand the work he did in his first few months as Sunderland manager (above), I know that he can have an extraordinary effect on a dressing room.
"However, it is the knowledge and wisdom of Martin O'Neill that will drive this Ireland team towards the Euro 2016 finals and I'm convinced we will qualify after the great start we had in Georgia a couple of weeks back.
"There may come a day when the Republic of Ireland manager's job is ready-made for Roy, but let's not kill off Martin just yet. He still has so much to offer and it's great for Ireland to have him as our manager."
