Melbourne: Andy Murray says his back is holding up well as he battles the energy-sapping hardcourts in his quest for a first Australian Open title in Melbourne, crediting the compression garment he is wearing.
The British world number six came through his latest test, a gruelling three- and-a-half hour four-set win over rising Bulgarian star Grigor Dimitrov on Sunday to take his place in the last eight.
The tournament has been a heartbreak Grand Slam for the Scot with three runner-up finishes, but he gets his chance to edge closer to the title with a tricky quarter-final against teenage local hope Nick Krygios on Tuesday.
The Australian Open can be physically demanding with long matches on the unforgiving hardcourts amid high summer temperatures, but so far Murray is feeling in good shape.
He has thanked wearing a compression garment for protecting his troublesome back, having had surgery on it in September 2013.
"My body allowed me to play that way for the whole duration of the match. I didn`t feel tired," he said after showing great fighting heart to claw back from 2-5 down in the fourth set to beat Dimitrov on Rod Laver Arena.
"I felt fresh. My back felt good. I wasn`t feeling stiff at all.
"I don`t normally say stuff like this, but for me the compression garments that I`m wearing just now are genuinely exceptional.
"In these conditions over the last couple years I struggled a little bit, and I felt absolutely fine.
"Whether or not it was the best match I played (since back surgery) -- considering it went three and a half hours -- it definitely felt way better than the last year or so.
"Physically, I felt completely different to how I felt at the US Open last year or even here last year when I played a long match, especially in cold conditions. It was like night and day."
Two-time Grand Slam champion Murray is bidding to track down an elusive Australian title after losing to Roger Federer in the 2010 final and Novak Djokovic in 2011 and 2013.