The five-time finalist was outplayed in a 6-4 6-2 6-2 defeat that was a far cry from his glory days and he looked emotional as he gave a lingering wave to all sides of Kia Arena.
It was only Murray's second opening-round loss at Melbourne Park in the last 16 years, with the other coming five years ago against Roberto Bautista Agut after the Scot had revealed that hip problems could mean the end of his career.
Surgery and a gruelling recovery process has given him a commendable post-script, but Murray did not dispute that this much more low-key exit could signal his final goodbye.
He said: "It's a definite possibility that will be the last time I play here. I think probably because of how the match went and everything. While you're playing the match, you're obviously trying to control your emotions, focus on the points and everything.
"When you're one point away from the end, you're like, 'I can't believe this is over so quickly, and like this'.
"In comparison to the matches that I played here last year, it's the complete opposite feeling walking off the court. I wish I involved the crowd more. Just disappointed with the way I played and all of that stuff. (It's a) tough, tough way to finish."
Murray admitted at the end of last season he was not enjoying tennis, and it is increasingly hard to see him finding the sort of performances and results that will bring the joy back.
This was his fourth defeat in a row dating back to October and he has lost seven of his last eight matches – the worst run of his career.
At the Australian Open last year, Murray conjured two of the more memorable occasions with five-set wins over Matteo Berrettini and Thanasi Kokkinakis, and there was optimism he could achieve the sort of results he has been striving for.
The 36-year-old is now struggling to hold on to that belief, saying: "I know in the last week, 10 days, how well I was playing against the best players in the world. That's why it's so frustrating that on the match court it's not there.
"I've been telling myself that at some stage it will. But obviously when you have performances like today, or a batch of results over a period of time like I have done, it's tough to keep believing in that."
Murray has said previously he has an idea of when he would like to retire, but he admitted that date could be brought forward.
He added: "I know that Tomas is a really, really good player. I'm aware of that. Even if I play well today, I can still lose the match. It's just the nature of the performance that makes you question things.
"I haven't gained in belief from today's match that at some stage I'm going to start playing really well again or winning tournaments or getting to the latter stages of major events.
"Last year was a slightly different story. Physically I held up well against two really good players. It's a very different situation sitting here. So the timeframe narrows a little bit for me to get to a level that I want to be at.
"I've spoken to my family about it. I've spoken to my team about it. They're very aware of how I feel about things, where I would like to finish playing, when that would be.
"I haven't made any definite decisions on that. It's obviously something that I need to think about and see exactly when that is."
Murray and Etcheverry shared two close matches last season and the Scot knew to expect long, punishing rallies from the baseline.
There was little to choose between them in the first set, with Murray missing one chance to lead 4-2 when a lob fell short before Etcheverry broke.
Murray's serve misfired from the start and his groundstrokes became increasingly wayward as the hopes of the former world number one and the supportive crowd faded away.
