Adam Johnson turned down approaches from Tottenham and Liverpool to join Sunderland as he seeks to boost his England chances.
• O'Neill hopes for Johnson impact
Johnson, 25, had spoken of his frustration that his lack of opportunities at Manchester City had cost him his place in the England squad for Euro 2012, and he is hopeful that the opportunity to play regularly at the Stadium of Light will turn things around.
"Roy Hodgson said he wants his players to be playing regular first-team football," he said. "That's something I wasn't doing at Manchester City, but I hope it will be different for me here at Sunderland.
"You do get seen more - and have better opportunities to be seen - by England managers when you play for top-four clubs, it's a fact, but I'm part of the England set-up and I'm hoping that won't change."
Johnson has been called up to the squad ahead of the World Cup qualifiers against Moldova and Ukraine - but Martin O'Neill says he would prefer it if the winger was staying on Wearside.
"I would prefer that nobody played during that break, but I am well aware that international football is predominantly very, very strong now," O'Neill said. "It takes precedence over almost everything at the moment."
O'Neill believes Johnson has earned the call-up to represent his country.
"As a club manager, all you do is just worry for about a fortnight until the players come back. But from Adam's viewpoint and for all the other players called away, it's great. It's great to play for your country, fantastic.
"England particularly now are involved in the build-up, their main games now in the World Cup, and it's good that Adam is part of it. He deserved that. Regardless of whether he signed for us or not, he deserved that on his performance in the friendly game [against Italy], albeit it was a friendly match."