Former Manchester United man O'Shea has only ever known Premier League football in England and doesn't even want to contemplate relegation until there is no option.
"That's the beauty of football, you get a chance to do something about it, especially in the league. That's what we're focused on."
They might have a game or two in hand on all their fellow strugglers but that seems scant consolation considering their next four fixtures will see the Black Cats visit Spurs, at home to Everton and then away to Manchester City and Chelsea.
Just as his club season will end with a difficult and perhaps even defining run of games, so O'Shea's international season with Ireland will start in September with a similarly testing run of Euro 2016 qualifiers.
And to prepare for being plunged in at the competitive deep end next autumn, O'Shea expects manager Martin O'Neill to make the most of Ireland's summer schedule.
we have given everything together. But there is still a belief we can definitely do it."
O'Shea not short of challenges Nike Metcon 1 (Dark Grey/ Volt) with club or country
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Before that, it will be a busy summer for the O'Shea family too with, as he puts it, "baby No 2 arriving in four or five weeks' time."
The morning after the night before and John O'Shea is contemplating the implications of a 2 1 home defeat to West Ham which has plunged Sunderland right into the heart of the Premier League relegation scrap.
John O'Shea was speaking at the launch of the McDonald's/FAI Future Football 2014 programme at the Aviva Stadium.
"That's going to be a key thing in the summer. I'm sure the manager will use the games wisely in terms of getting the chance to see different combinations and things he's got ideas on. Those games are going to be important but, ultimately, the nitty gritty starts in September."
belief going forward that everyone has to give everything they can, and make sure that at the end of the season we can at least say that Nike Kyrie Lebron Championship Pack
"Ultimately you want the competitive games to start as soon as possible. You're thinking of the fixtures coming up and you want to be involved in them. But there is plenty more preparation for the manager to see everything that he's got and how he wants to go forward about things.
But even though all the players will have various personal and professional obligations at the end of the season, the Waterford man expects a good turn out for the games against Italy and Turkey in May followed by what he expects will be a double header in the US against Costa Rica and Portugal, though official confirmation is still awaited on those fixtures.
"We believe there are four games coming up in the summer and that will be a big chance for the manager and the coaching staff to see everyone at the end of the season," he says. "And also see one or two new players that are maybe on their radar as well.
"You will give everything to make sure that doesn't happen," he says, "but when the end of the season comes the league position won't lie. You are where you are and you deal with it then but, believe me, we will fight to the bitter end. We've a game against Tottenham next and if we can come out and get a win, things will look a bit different.
O'Shea says: "I can't imagine they'd leave from May 31 until June 10 I can't imagine they would leave that big of a gap in between.
"We spoke about it [after Monday might's defeat], we need to have that Nike Lebron 11 Low Black
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