Former world number one Andy Murray said he would love to play Novak Djokovic, Rafael Nadal and Roger Federer before they retire, but only if he is capable of beating the 'Big Three'.
Murray looked set to retire following January's Australian Open, however, the three-time grand slam champion is on the comeback trail after hip resurfacing surgery.
The 32-year-old – who dropped down to ATP Challenger level to take part in the Rafael Nadal Open having skipped the US Open – is set to feature at the Shanghai Masters after accepting a wildcard.
Murray will spend a couple of weeks in the Far East, competing in the Zhuhai Championships and China Open as he eyes next year's Australian Open following a brief ATP Tour singles return in August.
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Asked about renewing his battle with Djokovic, Nadal and Federer, Murray – who has played doubles this year to build his fitness – said: "I look forward to doing it if, physically, I am capable of competing with them.
"I don't look forward to going on the court against one of those guys and not feeling like I have a chance of winning which, if I played them tomorrow, that's how I would feel.
"When I practised with Novak in Australia at the beginning of this year, I found that hard, even though it was just practice. I felt terrible and I found that quite hard.
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"If I'm able to compete against them and feel like I can win, even if it's a really small chance, then I will enjoy that, for sure. But, not feeling like I can be competitive and getting pumped, I probably wouldn't enjoy that."
Murray – now ranked 415 in the world – added: "I need matches just now. My body needs to build up some level of robustness. That's the reason for entering the [four straight] tournaments.
"And if I'm not getting matches [because of early defeats in each event] I'm at least around, practising with top players, getting my body more used to the speed and things."