I am not absolutely sure Andy clay doesn't interest much though he pretends to like it lol but nothing comes from the heart. On other hand, he just glows when he sees grass and loves hard too. Very parallel to Sampras in this regard. They have another similarity. Both can't be bothered with the lesser ranked players and typically tend to play as good as they need to. Andy goes one step further and gives a lackluster performance more often than not. lol. Sampras would just go for one break in each set and since he had a great set of serves, he'd typically get it. Andy had to of course had to pay the price for it a few times. But when they are faced with players who are best in the business, they tend to bring their best as well. Both thrive on a great atmosphere as well. Big crowd, big occasion etc. Of course Andy is not even half way there as Sampras but it's interesting to notices common things between them.
But I'd rather Andy takes each of his opponent very seriously. I don't think he can afford not to. Neither can Nadal or Nole. Perhaps only Federer since he's got a great set of serves as well which he can rely on pretty easily.