For O'Shea, it was the gateway to more regular involvement for his country and, as captain for this evening's meeting with the same opposition, the hope is that it proves as significant a landmark for some of his young colleagues.
He is well-placed to comment on two players who are likely to be a major part of Ireland's next generation. Giovanni Trapattoni's positive decision to start with natural wingers James McClean and Robbie Brady puts two promising figures in the spotlight.
Considering that he plays his club football next to McClean and knows what Brady is going through in trying to impress Alex Ferguson, the Waterford man has valuable advice to impart.
With regard to the latter, he welcomes his decision to join Hull on loan for a second time; stints at Bournemouth and Royal Antwerp prepared O'Shea during the embryonic stage of his Manchester United career.
"Look," he said, "Robbie is a very intelligent lad. He is under no illusions that he is facing a very difficult task.
"He needs to get a run of games into him to show when he goes to Hull that he is more than capable of playing at that level and showing his talent, as he did last season. After that, he got a few more chances when he went back (to Manchester United) in pre-season, and a couple of League Cup matches.
"He has got a lot of ability and he has got the talent to back it up, so if he did get a chance to get a run in the Manchester United team, I'm sure he'd take it with both hands. But, as I said, he's got a lot of competition."
His confidence has not gone unnoticed. "It definitely helps you," he continued. "He has got a fantastic left foot and he is very creative.
"He'll get the chance against Greece to show that, hopefully, and take another step forward."
Brady was tipped for stardom from his teenage years and his progress, while relatively quick, has been more gradual than McClean's, who suddenly shot to fame less than a year ago and has dealt with all sorts of attention since then.
His club boss Martin O'Neill acknowledged recently that the Derry lad was perhaps suffering with a bit of the dreaded 'second-season syndrome'. However, O'Shea feels there has to be greater collective responsibility for the 23-year-old's underwhelming start to this season.
"We should all be doing a lot better," he countered. "It's not just about one individual.
"James has come on in leaps and bounds. He was the surprise factor last season; he came in when the manager took over, got into the team and took everything right in his stride.
"You are obviously more aware of a talent like that and now teams are marking him more tightly, they are doubling up on him.
"The manager left him out for a few games there as well because of the quality of the squad. But it's up to us to get the ball to James in better positions, get it to him quicker so he'll be in better situations and can show us the talent he undoubtedly has."
McClean recently admitted that his international woes had affected his morale, a reference to the ill-advised tweet in Kazakhstan that angered Trapattoni and senior players, including O'Shea.
That effectively cost him a start in the September friendly meeting with Oman.
The stand-in skipper feels the call for this fixture could raise spirits. "Any time any young player plays for their country, it's going to give him a boost," O'Shea stressed. "And I am sure, knowing the type of character James is, he will take it all in his stride."
O'Shea recalled little from his own Greek experience.
"The weather was nice, that was about it," he grinned. "I don't think it was a very memorable game otherwise."
Significance was drawn from the consequences. "It's important for the youngsters to show their increased ability," he continued. "The manager has given them the chance on a special stage."
It's up to the wide boys to take it.