Perth:Australian third Test hero Ryan Harris admitted he was "surprised" how well he was playing with a chronic knee injury that is degenerating with virtually every ball.
The stocky, unheralded right-arm paceman is a latecomer to Test cricket, but the 31-year-old is determined to make the most of every chance he gets at the top level.
And he certainly did so at the WACA Ground, claiming 6-47 in the second innings to power Australia to a 267-run victory that levelled the series.
Harris's career highlight, in just his fourth Test, came while he battles a degenerative problem in his right knee that needs corrective surgery.
"If I was 21 I'd get it done but I'm not, I'm 31 and it's a 12-month recovery, so for me to have that I think would be the end of my career," he told journalists on Sunday.
"Basically the cartilage on the outside of my right knee is going, basically there's not much left and I'm eating through it every time I pound into the crease. It's just a management thing and I'm going well at the moment."
Harris had arthroscopic surgery earlier this year and suffered such soreness when he returned to first-class cricket in October that he doubted whether he would be able to play four or five-day games again.
He can barely believe he is playing in the Ashes series, let alone preparing for his first Boxing Day Test at the renowned Melbourne Cricket Ground.
"Leading into this series I was hoping to take part in it, but obviously with my knee the way it was, I wasn't sure if I was going to be a part of any cricket this summer," he said.
"After I played my first (Sheffield) Shield game back in Tasmania, I had massive doubts about whether I could even play four-day cricket, it just blew up big-time.
"So at the moment it's a great feeling, obviously to level the series to get it back to 1-1 and to obviously take six wickets in an Ashes Test is a great feeling.
"I'm surprised more than anyone at how it (knee) is reacting. Everything is going great at the moment."
The powerful right-armer said he was sure to be nervous before the fourth Test.
"Watching a Boxing Day Test, as an Australian you get shivers down your spine, let alone actually playing in it," he said.
"The thought of it actually gets me nervous, it's going to be an amazing feeling if I'm picked.
"It's going to be a great feeling, especially now with the series 1-1," he said. "Obviously I think a few people thought it may have been a dead Test, the last two Tests, but there's a lot more on it now."