"Is it him?" "I thought he was injured?" "Is he playing here?" "Who is he playing?"
The questions from spectators highlighted the surprise element at the Mubadala World Tennis Championship on Thursday afternoon.
Andy Murray was not scheduled to be among the six participants competing at the International Tennis Stadium at Zayed Sports City, yet there he was, the three-time major winner, out on one of the practice courts.
The former world No 1 spent almost 90 minutes being put through his paces by Jamie Delgado, a lead member of the Briton's coaching staff in front of a growing crowd of spectators.
The session had not been advertised to the public, but word of mouth spread in the early afternoon that the Murray was at Zayed Sports City and would be on court.
Murray is in the capital on a stopover en route to Australia with an eye to playing in the Brisbane International, which starts on Monday, ahead of what he ultimately hopes will lead to competing at the Australian Open in the middle of next month.
Murray, 30, has not hit a competitive ball in anger since he lost in the quarter-finals at Wimbledon in July to Sam Querrey, in visible pain with a hip injury as he did so.
Murray then missed the US Open in September, pulling our 48 hours before his opening match. He has sat out the rest of the season to try and deal with the hip ailment and the world No 1 slot has long been lost. He now 16th in the ATP rankings, his lowest position since May 2008.
The session at Zayed Sports City, a venue Murray is familiar with having won the Mubadala title twice in the past, appeared to be designed to not only test the Briton's mobility but also his stamina.
There were regular breaks throughout to allow Murray to sit down with Delgado and ruminate, presumably on his physical state. Murray often looked weary after a short intense period of moving around the court hitting shots, completely understandable, of course, given his long injury lay off.
As body language goes it was not the most positive sight, but taken in context with regards to the recovery process, completely understandable.
It was interesting to watch Delgado test various parts of Murray's game.
Things began slowly with some gentle rallies, designed to move Murray around the court, but the intensity built up as the session went on.
While initially a little rusty, Murray hit the ball cleaner and cleaner on both his forehand and backhand, and after starting with some rather basic serves, he was able to put more power into later efforts.
Murray's court coverage was also tested with Delgado dropping some balls, by hand, at the net which Murray, for the most part, successfully chased down.
This was a serious session and other then a few encouraging words and instructions from Delgado, and the occasional verbal grunt from Murray as he stretched to return a ball, there was little in the way of any dialogue.
Murray did acknowledge the spectators with a wave when his was finally done as the sun began to slowly set on the practice court.
Only he will know how his body is feeling and holding up. But on the balance of what was on show in Abu Dhabi, he may be able to play in Brisbane and in Melbourne at the Australian Open, but it may take a lot longer than mid-January for the player who was good enough to be the highest ranked player in the world 12 months ago to return to that level.
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