like that Fed t-shirt, thats his 2010 Aussie Open shirt
It's his day shirt from this year's AO. Because he only played one day match he barely got to wear it so clearly he wanted to put it to more use
His 2010 shirt was a slightly different colour and had white markings where this one has black. I prefered it to this one.
If you can't tell Federer outfits are something of a specialist subject of mine