Forget the forehand Federer, what about the queen?

On a sleepy Roland Garros afternoon, Roger Federer found himself discussing life lessons in tennis, carrying the Swiss flag at the Olympics...and Queen Elizabeth's diamond jubilee.

It's been nine years since the great Swiss last lost a Grand Slam match before the third round stage, so he is not surprised when faced by questions which have little to do with the business just completed.

So it was on Wednesday as Federer moved into the last 32 of the French Open with a four-set win over Romania's Adrian Ungur with a record-breaking 234th Grand Slam match win.

"In the beginning, when you think you're good but maybe you're not that good yet, you get many surprise losses," he said, as painful memories of earlier visits to Roland Garros came flooding back.

"They hurt you. I have had a few here -- against Arazi (2002), Horna (2003). Against Gustavo Kuerten (2004, third round), I was the favourite. I thought his hip wasn't good and he came off a five-setter and I lost in straight sets."

Playing in his 50th straight major, the 16-time Grand Slam title winner has got used to post-match inquisitions often taking on a significance far outweighing the occasion.

"There is a different momentum in the press conferences. That's the toughest part sometimes."

And so it proved on Wednesday as his Roland Garros chances were quickly to put to the side in favour of the Olympics and his dining habits with members of the British royal family.

Will he be carrying the Swiss flag at the London Games for a third successive Olympics?

"I haven't heard officially yet. I have heard rumours and I would love to do it. I have done it twice in Athens and Beijing. It's a dream for me."

The Olympics tennis tournament is being held at Wimbledon where Federer has already won six titles.

It was also where he met and lunched with Queen Elizabeth II in 2010 as the British monarch visited the All England Club for the first time in 30 years.

The British media wanted to know what he thought of the queen's 60 years on the throne and his memories of meeting her ahead of jubilee celebrations this weekend.

"I have had lunch next to the Queen. That was exciting. It was a big honour. She watched Andy Murray and I think they even scheduled the whole thing around her.

"She was very sweet, very nice, very polite, of course, and just a pleasure to be around."