The 92-cap Australian back has not given up on playing international rugby again, but acknowledges a return is unlikely since moving to Toulon.
Giteau remains a Wallaby in waiting
Spectators at next month's Dubai Rugby Sevens will be treated to an experience which has become disconcertingly rare on an international playing field: the sight of a Giteau in full flow for Australia.
Unfortunately for those who believe the multi-talented Matt has been cut off in his prime, it is older sister, Kristy, rather than he, who will be gracing the fields at The Sevens.
The burden of such a famous family name weigh heavy, for a player representing the world champion Australians in the inaugural IRB womens tournament in Dubai, but she has broad shoulders.
"She is tough, but you have to be with three brothers," Giteau, 29, says. "We didn't treat her any differently - if anything we were a bit rougher on her."
Giteau was a star of the sevens game himself, before embarking on an international XVs career which climbed great heights, before reaching what appears to have been such an unsatisfactory terminus this year.
He has not given up on adding to the 92 caps he has won for the Wallabies, though he acknowledges a return is unlikely.
He is on his way to play for Toulon in France, making him ineligible for the Wallabies because he is no longer contracted to an Australian province.
However, he has had it written into his contract with the French club that he can be released for international duty if the rules on overseas-based players are relaxed.
But that is only part of the problem. "You obviously have to be selected as well, and that seems to be a bit of a challenge as well at the moment," he says.
Robbie Deans, the Wallabies coach, had enough chances to recall the France-bound centre during the World Cup. None was forthcoming.
Australia were hit by a succession of injuries during the competition. However, when the calls went out for new recruits, none was made to Giteau - even though he was already working in New Zealand as a media pundit by the time the quarter-finals came around.
"Initially, I didn't even want to watch it," Giteau says. "I'd say, OK, I'm not going to watch it this week, then you end up watching it because you have mates involved.
"You are still really interested. By the time it got to the quarter-finals, I had gone to New Zealand, was doing some commentary work and started enjoying rugby for what it was: a game."