BBC's tennis commentator and pundit Andrew Castle believes that Andy Murray may never be able to recover from his hip injury.
Murray was diagnosed with the issue before attempting to defend his Wimbledon crown this past July, his last competitive match on a court being the quarter-final loss to American Sam Querrey four months ago.
After Murray went head-to-head with Roger Federer in a charity match at Glasgow’s SSE Hydro on Tuesday, the Scot himself admitted he will only return to tournament action when he is ready.
"I felt pretty good - not perfect but I felt like I'm going in the right direction,” said the 30-year old, who has dropped to a world ranking of number 16 due to his enforced absence.
He added: "I'll come back when I'm ready and 100% fit. I believe I will get back to that."
But Castle, a former British number one, saw a completely different Murray from his view point.
"From the evidence of my eyes, it doesn't look like his hip is good at all,” said Castle to BBC Scotland.
"The way he's moving, changing direction, he's clearly uncomfortable.
"I was disheartened to see that he hadn't made much progress in terms of the way he was walking between points - more than four months on.
"I'm not trying to be negative and I was delighted to see Andy back out on the court, he's given us so much joy over the years.
"To be quite honest, I'm just not liking what I'm seeing."
Despite this view, Castle doesn’t believe it has come about due to a lack of effort, more so it is the nature of the injury to the hip that he suffered earlier in the year that is destabilising three-time Grand Slam champion Murray on the court.
"I know he's training hard and doing all the physical work,” Castle added.
"The fluidity of movement is certainly not there at the moment. Perhaps it won't keep him off the court for ever. I'm not a medical person.
"He's always kind of loped around, then burst into life during points. The physical element of his game has been extraordinary.”
And with Murray’s wife Kim giving birth to their second child today, a girl, Castle isn’t sure whether the addition to his family will impact his decision when to return to the court.
Said Castle: "He's 30, he's a father of two. He's done so much. None of this will lessen his desire to get back but I didn't feel positive watching him last night.
"If you can't sprint or change direction, then it's going to be very difficult.
"If that hip issue wasn't there, he'd have another five or six years because he is such a thorough professional.
"If we've seen the last of him at the top level, then that's a real shame."
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