Quadruple Olympic champion Mo Farah
The 39-year-old Briton compared himself to former tennis world number one Andy Murray, saying the Scotsman still had the "fight" in him.
However, his body might be telling him the game is up.
Farah moved up in distance to the marathon -- winning in Chicago and finishing third in London in 2018 -- after he had won double Olympic gold in 2012 and 2016 at 5,000 and 10,000 metres.
He moved back to the track in 2020 as he aimed for an Olympic finale but was a shadow of his former self and failed to qualify for the Tokyo Games.
Things did not get better this year as he was beaten by a club runner on his return to action at the London 10,000m in May.
However, the Somalia-born track legend is unwilling to hang up his spikes yet and is going to test himself in the London Marathon on October 2, and the tune-up London Big Half event a month earlier.
"Do I still have the hunger, am I willing to put in the work and the miles? Yes," he told the Daily Mirror.
"I still have that fight in me and until you lose it I don't think I should think about retiring.
"But being realistic, can my body do this?
"I've watched tennis and Andy Murray, the guy still has that fight in him but his body doesn't allow him.
"I'm still doing sessions normal people can't do. You still feel you've got it but you have to be realistic."
Farah -- who also won six world outdoor titles -- says his mind might tell you to go on but sometimes a period of reflection is required.
"You think you've still got it because that's our mind at this level," said Farah.
"You don't think anything other than you still got it. But sometimes you've got to take a step back, be realistic.
"The truth is I am getting on a bit and sometimes your body doesn't allow you to do things.
"But that's also the reason I'm not going to the World Champs or Europeans this summer."
Farah, though, is adamant when it comes to retiring it will only be him who makes the call.
"That decision can only come from me, not my manager, not my wife or my kids," he said.
"There will be a time, but I don't even know it myself."
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