"I got up and felt my mouth. At first I thought I'd lost some teeth and I just kept playing on for a bit.''
In fact, McKendry didn't just stay on the field for another few minutes but he also made two tackles after the injury.
"I realised then that something wasn't quite right. I could feel part of my jaw moving around.
"It's a setback but it's just one of things. That's football. It's the first time I've broken anything.''
He had suffered a break on the point of the jaw and there were also fractures of the lower mandible on the right side of his face, leaving his bottom teeth out of alignment. After the game he was taken to hospital in central London for a delicate operation.
Mayhew said the specialists were delighted with McKendry's progress after seeing him today.
"Both the plastic surgeon and the dental surgeon who operated on Saturday night saw Sam today,'' said Mayhew.
"They said the outcome of the operation had been excellent. Sam is due to see them for another check-up next week.''
McKendry had earlier been keen to fly home to Sydney as early as possible if he had been cleared to fly following the operation but he said he now wanted to stay on.
While his diet is limited at this stage, he said he could feel improvement and he was able to eat some soft foods and drink fluids.
"I've been told I should be right to return to full training in eight weeks and I should be able to start running again fairly soon,'' he said.
Kopczak was originally facing a one-match suspension for a dangerous shoulder charge handed down by an International Match Review Committee. However, the Welshman was let off with a caution, leaving him free to play against Australia in the Welsh side's final Four Nations match in Wrexham on Sunday.
McKendry was also the victim of a high tackle in the 15th minute of the encounter with Wales. It left him needing treatment as blood poured from his nose but, like Kopczak's shoulder charge, it went unpunished by referee Matt Cecchin during the game. The match review committee later issued Welsh hooker Neil Budworth with a caution over the tackle.