Tim Henman believes Andy Murray has still got the hunger to fight his injury problems and return to the ATP Tour.
Murray's comeback from hip resurfacing surgery last year looked to be going well as he won the European Open in Antwerp, but 2020 has been a wretched year.
An injury related to his hip surgery curtailed the early part of the year before the coronavirus pandemic kept him off court until September, and he only played seven matches before more injury issues ended his season early.
The 33-year-old has found himself back in rehabilitation and restricted to the practice court, but Henman says the fires are still burning.
"He has had an incredibly difficult last three years, trying to fight his way back from his hip injury," Henman told the PA news agency.
"There are signs that he is making improvements and then he has another little setback. He will be desperately keen to get back to playing but he has just got to build up his strength and stamina and hopefully competing on a consistent basis.
"The tennis level is there, it is just whether his body can maintain. We saw him beat (Alexander) Zverev, who went on to get to the US Open final so Andy is still capable of playing great tennis, but that is not his challenge.
"It is the challenge of being able to put in the work on the practice court and being able to play these tough matches and recover to be ready.
"I was speaking to his coach Jamie Delgado and he mentioned his discipline and hunger and desire is amazing because these elements of the rehab are not the enjoyable bits.
"The enjoyable bits are being out on court and playing tennis and competing in the biggest tournaments. He still wants to keep working and hopefully things will be a bit smoother in 2021."
Had his career-defining injury not struck, Murray would have ordinarily been preparing for the end-of-season ATP Finals, which take place next week at the O2 in London for the final time.
It was there where Murray's career peaked in 2016, winning the final against Novak Djokovic to finish year-end world number one.
Henman, who will be commentating on this year's tournament for Amazon Prime Video, ranks that moment as his highlight of the last 11 years of the event being in London.
"It is the end of an era of the ATP Finals at the O2," he said. "(Roger) Federer has won a couple of times, Djokovic has won four in a row, there has been some amazing ends to the year.
London & @TheO2 have become a second home for @djokernole 🎾 He gives us his favourite memories from the #NittoATPFinals! — ATP Tour (@atptour) November 9, 2020
"For me Murray winning in 2016, he had been on such a hot streak, for it to go down to the final match of the year, playing against one of his biggest rivals in Djokovic, the final match to decide not only the champion but also the end of year number one.
"For Andy to win that in front of his home crowd was special."
Djokovic will be going for more glory this year alongside Rafael Nadal, Dominic Thiem, Alexander Zverev, Stefanos Tsitsipas, Daniil Medvedev, Andrey Rublev and Diego Schwartzman.
Henman thinks the current world number one, who has already booked his place at the top of the year-end rankings, will triumph.
"If I had to pick one it would definitely be Djokovic," he added. "He has got the year-end number one, but now he is looking at the total number of weeks to try and take Federer and I am sure he will get that next year at some stage.
"He didn't play in Paris, he looked flat in Vienna, but this is going to be a different kettle of fish."
:: The Nitto ATP Finals will be available to watch on Amazon Prime Video on Sunday 15th to Sunday 22nd November
