I think that a lot of you are missing the point that the author was trying to make: Tennis needs Nadal right now because he is the only one that can cause Fed problems.Ok,no player will ever be bigger than the sport but let's be real about,tennis for the time being still rests on the shoulders of the Fed/Nadal duo.Fortunately we have young guns like Murray,Djokovic,Del Potro,not to mention veterans like Hewitt,Roddick and so on,but in the end most people still want Nadal-Fed matches because of the rivalry.
I don't think Montreal will be that relevant.Nadal is coming off knee injury and Fed has just become a daddy.However USOpen will lose some of its shine if Rafa doesn't show up.Again,this doesn't mean that we can't have great matches.For me the best match of WB 09' was Murray-Wawrinka and neither Fed or Nadal were a part of that.
But while we get entertained on the way to the final by the lower ranked players(and I used lower ranked loosely,because top 20 are very good players),most of us want to see the interesting match-ups from quarters on.And although some guys put up a great fight(like roddick this year) the outcome most of the times is that Fed wins,at least for the past five years.And I'm not just talking about the USOpen,I'm talking about most of the tournaments he enters.While this is great for Fed and his fans,for the rest of us it's boring.Tennis needs some unpredictability.Nadal has provided that for the last 4 years(if it were not for him Fed would have about 18-19 freaking slams) while the others have failed,at least at the Slams.
That being said,I think Murray and Roddick will be Fed's problems at this USOpen,not Nadal whom we haven't seen play since may.But still,Fed is favorite by a country mile.