For the 31-year-old Parker, the last-eight match against the 2006 World Cup winners represents a landmark moment in a slow-burning career punctuated by periods of high promise and ultimate frustration.
"For me, this is what it is all about, what I have always wanted," he told a news conference on Friday. "Yes, it has been tough to make progress here... but me and Stevie [Gerrard] are relishing it and long may it continue."
Parker, ever present in England's three group games, should win his 17th cap against Italy but his own modest assessment of his ability means he is taking nothing for granted. He plays without personal ego and talks in the same way.
In an England side coach Roy Hodgson has made durable and difficult to beat, Parker is an unsung hero, a tackler who reads the game and makes covering runs to free midfield partner Gerrard and others to create chances.
Seventeen England appearances in nearly nine years in the English Premier League tells its own story and in Parker's case it is unique because he won his first four caps with different clubs, Charlton Athletic, Chelsea, Newcastle United and West Ham United, between 2003 and 2011.
From 2007 to 2010, he was not selected by England but he never gave up and the dogged persistence that has characterised his career has manifested itself on the field. In many respects, he has become the heart of England's team at Euro 2012.
On Sunday, he faces one of Italy's greatest midfielders, Andrea Pirlo, a master tactician who can command and control a game with his technical ability and range of passing.
For Parker, it is the challenge that confirms his arrival at the pinnacle of European football.
"I am really looking forward to this," he said.
"When you play football, this is what you want to do - to pit your wits against the very best. And that is what he is... his passing ability and control of the game is fantastic.
"To play Italy? This is what we are here to do. It is what we want to be doing. Look at what we are up against - a team with buckets of experience and a lot of great players, very well disciplined, organised, prepared..."
For Parker, there will be only one way of containing Pirlo if the Italian playmaker ventures into his territory and that will be to press him backwards or win possession with a trademark snappy tackle.
When France won the World Cup on home soil in 1998, they had in captain Didier Deschamps a similar player, famously dubbed as "the water carrier" by compatriot Eric Cantona.
It was a role in which another Frenchman Claude Makelele excelled for France and Chelsea who signed Parker, in 2004, as his potential successor.
In his one season at Stamford Bridge, however, Parker had few opportunities and struggled to establish himself just as he did initially with the national team.
But Parker is nothing if not tenacious as Pirlo and Italy will find out.
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