Federer and Del Potro
Bionic Poster
Kohl has also beaten top guys in slams, including crushing Djokovic in straight sets at the 09 French where he would have a good shot at the title otherwise with Nadal losing. I could be wrong but I dont believe Dolgo. has. So of the two that was the better shot of an upset or atleast a competitive match, even if still not much.
That's the main reason I believe Nadal hasn't gotten many night matches, because his draw completely collapsed. It isn't that Nadal isn't a hot sell crowd/ticket wise, it's that his opponents have not been very marketable themselves.