"It's a different type of pressure," he said of Murray's new experience in returning to a slam as the title-holder. "On the one hand, he's done it – so that's amazing; on the other hand, you're the hunted more than you were in the past. And, if you combine that with Wimbledon, this is the first shot where he's got a legitimate chance to finish No1 and be No1 for the year if he can get two majors.
"So that's a different type of approach and people are going to be gunning for him even more. I think he's found that a little bit since playing Wimbledon. He's much tougher to beat in a best-of-five than he is best-of-three, so he'll be ready and I know that, after winning Wimbledon and getting ready to defend the US Open, he's trying to peak at that moment, so it's going to be interesting."
McEnroe – still hitting a tennis ball cleanly enough to look forward with confidence to playing again in the Statoil Masters at the Royal Albert Hall in December – adds: "There's three different guys – obviously Rafa [Nadal], Novak [Djokovic] and Andy – who between them have won the three majors, and all three of them feel that, if they win the US Open, they're going to deserve to be called No1 for the year."
John Isner, meanwhile, is the standout local hope, coming off three straight wins over top-10 players and an impressive performance in a close losing effort against Nadal in the Cincinnati Open on Sunday. Not surprisingly, the American thinks Nadal will be the hardest to beat in New York.
"I would say Rafa is the favourite going to the US, but clear-cut? I wouldn't say that. I think he'd probably say the same. If you compare maybe him and Serena [Williams], she is probably a more clear-cut favourite on the women's side than Rafa is on the men's side, but he certainly is going to be super tough to beat considering he just won back-to-back Masters events on hard courts. He has actually not lost a match on hard courts this whole year. He's got a lot going for him. And as always, the field is going to be extremely tough."
And Isner, with justification, did not totally discount his own chances. He is worth an each-way bet.
"For me, it's such an encouraging summer so far. The last few years I've played well leading up to the US Open. Again, that's the case this year. So I'm looking forward to that event, for sure."
"It's hard to choose between Andy, Rafa, Novak and Roger [Federer]," she said, "but I think I will root for Rafa a little bit more. It would be great to see him back and winning on hard courts."
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