Bautista Agut completed a 6-4 6-4 6-7(5) 6-7(4) 6-2 victory in more than four hours, sending him through to a second-round meeting with Australia’s John Millman.

From two-sets-to-love down, Murray had wrenched himself back into the contest, thrilling the packed crowd of nearly 10,000 at Melbourne Arena as he recalled the gritty warrior of a player who’d claimed three major titles and two Olympic gold medals.

This was to be his last Australian Open, he declared in a heart-wrenching press conference during which he revealed his chronic hip condition was simply posing too much pain to continue competing.

But his battle-weary body simply couldn’t carry him through five sets.

"I've honestly loved playing here over the years. It's an amazing place to play tennis. If this was my last match, (it's an) amazing way to end," Murray said on court. 

"I gave literally everything I had. It wasn't enough tonight."

Bautista Agut clinched victory thanks to a forcing forehand to end an emotional contest before the two men shared a heartfelt handshake on Murray's side of the net.

"Today was an incredible night," the Spaniard said.

"Andy deserves all the people who came to watch him ... it was an unbelievable match. Really good fight. He's a tough fighter, tough opponent, he gave everything until the last point. 

"I want to congratulate him for all he did for tennis."

- Australian Open