"The day before the (doubles) quarterfinals Roger lost to James Blake in the singles and I had to prove to him that he could trust me, " Wawrinka said.

CNN: Why Federer's friend is flying the Swiss flag at London 2012

Of course, I had my doubts that I was going to come through, having lost so many times in three sets against him.

BBC: Roger Federer enjoys return to top spot

Having left the Fed six years ago this month, I had lost track of the goings on in Ireland, so I tracked down my friend by email and asked him what happened to Ireland.

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