Five-time Australian Open finalist Andy Murray has bowed out at Melbourne Park for possibly the last time, going down in a thrilling 6-4 6-4 6-7 (7-5) 6-7 (7-4) 6-2 first-round loss to Roberto Bautista Agut on Monday.
Battling a chronic hip injury that has him on the verge of retirement, Murray put up a fight against the Spanish 22nd seed in the four-hour-and-nine-minute contest.
The 31-year-old Scot, who said he will assess his future in the sport after the tournament, had momentum heading into the deciding set but Bautista Agut broke in the third game before serving out the match.
Murray was left limping and in visible pain by the end of the fifth set, that earlier in the match looked long odds.
"If this was my last match ... l"I gave literally everything I had. It wasn't enough tonight," Murray said.
"Thank you so so much to everyone who came out tonight. I've loved playing here over the years."
Drawing on the support of a packed Melbourne Arena, Murray let out a trademark road when he took the third set in a tie-break.
He then took the fourth on another tie break after claiming a mini-break on the first point.
But Bautista Agut broke in the third game of the final set to go ahead 2-1 as the former world No.1's body finally gave way.
Murray, who slipped to No.230 after last year's hip surgery, has targeted Wimbledon as a fitting farewell to the sport but left the door ajar to an unlikely return to Melbourne.
"Maybe I'll see you again, I'll do everything possible to try," he told the crowd.
"If I want to go again I'll need to have a big operation and there's no guarantee that I'll be able to come back from it."
Triumphs at the 2012 US Open and Wimbledon in 2013 and 2016 and in two Olympic finals ensured Murray was no longer the bridesmaid of men's tennis, cementing his status as a member of the 'big four' alongside Federer, Rafael Nadal and Novak Djokovic.
The Scotsman's win at Flushing Meadows came after being a grand-slam runner-up four times and saw him become first British man to win a major since 1936.
Bautista Agut, who has lined up a second-round clash with Australia's John Millman, gave tribute to Murray post-match.
"It was an unbelievable match. He gave everything until the last point. I want to congratulate him on all he's done for tennis," he said.