He's won MC, Barcelona and Rome in straights. Madrid and it's blue clay was the one aberration. Winning titles without dropping a set isn't easy so wel done Rafa - clay God in business so far this season.
Last player to take a set off him on red clay - Del Potro.
"And still deeper the meaning of that story of Narcissus, who because he could not grasp the tormenting, mild image he saw in the fountain, plunged into it and was drowned. But that same image, we ourselves see in all rivers and oceans. It is the image of the ungraspable phantom of life; and this is the key to it all. "- Herman Melville, Moby Dick
Only Federer in the Roland Garros final (7-5) and Del Potro in the Davis Cup Final (6-1) managed to take sets off him in this period. Quite impressive, he hasn't even played that many tiebreaks either.