Andy Murray says he "gave everything" after he was knocked out of the Australian Open in the third round - and believes he can go further at future Grand Slam tournaments.
The British player lost in four sets - 6-1 6-7 (7) 6-3 6-4 - to Spain's Roberto Bautista Agut.
The defeat came after Murray's marathon second round match against Australia's Thanasi Kokkinakis - which lasted five hours and 45 minutes, finishing at 4am.
Coupled with a near five-hour first-round win over Matteo Berrettini, the Scot had spent 10 hours and 34 minutes on court just making it through to the last 32.
"I feel like I gave everything that I had to this event, so I'm proud of that," Murray said.
"I think even tonight, I'm competing against a guy who is 20th in the world, and it's still very tight considering the circumstances.
"I'm disappointed because I feel like I could have gone quite a bit further."
The match against Bautista Agut came four years after Murray revealed the extent of his hip pain and that he was considering retiring ahead of a first-round clash against the Spaniard.
"Obviously you never know exactly when the end is going to be," said Murray, who credited a rigorous pre-season training block for his improved form and fitness.
"I can have a deeper run than the third round of a slam, there's no question about that.
"Obviously draws can open up for you. I need to also help myself with that. If I was playing at this level last year, I probably wouldn't be ranked 50, 60 in the world. It's up to me to try and change that."
Murray was last British singles player at tournament
Murray was seen limping off the court as he made his way back to the changing rooms after the game.
This was the first time at a Grand Slam event since the French Open in 2017 that Murray has been the last British singles player standing.
Speaking after his victory, Bautista Agut said: "Always playing Andy in a grand slam is very tough. He knows the game very well and knows how to play a grand slam match.
"I'm very happy with how I managed all the nerves and all the tension during all the match. I played very good tennis and I'm very happy I got the win."
Coupled with a loss for Dan Evans to Andrey Rublev earlier, that is now the end of the British challenge in singles for another year at Melbourne Park.
Meanwhile, Novak Djokovic continued to defy a hamstring injury as a straight-sets victory over Grigor Dimitrov sent him into the fourth round of the Australian Open.