Pretty terrible. Arguably the worst Federer GS match.... maybe ever. Given it was epic on paper, but on of the most abysmal things to watch Backerer looking ready to give retirement speech right there...
It was a pretty crappy and injured version of Federer, so it's not as shocking as it normally would be.
That said, I do wonder if it was a semi-tank. I find it hard to believe that Federer would ever truly tank a match, but if he ever did, it would be that one.
I remember on the eve of that match I was thinking "Rafa finally getting a chance to play Federer at the US Open is too good to be true, so is there any doubt Federer will withdraw with a freak injury?"
I never even considered the possibility of Robredo winning legitimately....
I wouldn't rank it highly. Roger Federer was having a hell of a year and didn't look at all motivated, while Tommy Robredo did.
The fact that Tommy Robredo had 7(!) US Open R16 appearances could make one look at it either way. It's definitely ironic that it was against Roger Federer with whom Tommy Robredo was to eventually break his duck against.
IIRC Federer had tons of break points that he never took, Robredo was playing pretty well in 2013-2014 after his comeback and Federer had changed his racquet and looked dodgy so it wasn't insanely shocking, but still bizarre.
To be quite frank, I do not think it was too big of an upset. My reasoning is - excluding the French, which Federer rarely participates - the US Open has been Federer's weakest slam for over a decade. These losses are to be expected.
Also, Robredo was one of Federer's biggest rivals and reached a career-high ranking of number 5 in the world in 2006. He is no slouch.
I say the Millman defeat was much worse. That was the bigger upset. However, after how Millman played Federer close in Australia, and their 2015 match entered the final set, maybe it is a matchup issue for Federer.
One of the best of the 2000s never to make a slam SF.
Clearly not a great player.
And he's not a rival of Federer.
He fits into the category of bunny, and if he takes a set off Federer its considered 'impressive'.
Robredo took 3 sets in their first 10 matches.