At the end, he could barely lift his racket to acknowledge the enthusiastic support of the hundreds of spectators in Zhuhai’s impressive Centre Court arena.
The humidity, even at close to 10pm, was intense and his energy was well and truly zapped.
But undoubtedly, after his 6-3, 6-7 (6-8), 6-1 defeat of Tennys Sandgren which marked his first tour-level singles win since January 1, Andy Murray is back.
The proof came in a 13-deuce battle of wills in the middle of the third set.
Murray was at his sublime best, producing sublime drop-shots and cruelly-disguised lobs.
The 32-year-old was not thinking about his horrendous recent past or what he can achieve in the future. He was living in the moment.
And it was all too much for Sandgren, a useful American ranked No 68 in the world who had beaten Murray in straight sets exactly five weeks ago.
Murray was rusty to begin with. When chasing down drop shots, he was unconvincing. When Sandgren followed that with a lob, he was positively ginger. But a lot of it appeared to be in the mind.
He let slip a match point in the second set and was clearly annoyed with himself.
That is when three-time Grand Slam champion Murray can be at his best. The energy he showed in the third was irrepressible – certainly from Sandgren’s point-of-view.
Throw into the mix a 135mph ace in the first set which was as quick as Murray ever usually managed at his grand slam-winning best and physically there does not appear to be very much wrong.