Tough? Undoubtedly.
But right now, Nadal is the toughest.
I am not trying to sound lame/cliche/whatever but that's part of what the French is all about.
It's a f***ing tough major to win and right now, Nadal is the man to do it.
It is going to be tough for anyone but it's the least tough for a [healthy] Nadal by a nice margin.
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Congratulations to Rafael Nadal on a Career Golden Slam. - The Mana Sword