He played on for another 10 minutes, telling the on-field doctor the pain was more in his shoulders. After an interchange spell, he even returned for another stint before succumbing to the pain. The next day, scans revealed he had fractured the C6 vertebrae in his neck.
"I was very lucky," says McKendry. "I really didn't realise how serious it was. I remember asking the doctor in the changing room, 'am I fit to play next week?' He said, 'no, sorry'."
McKendry says retirement never crossed his mind.
"There was some uncertainty when I saw the neurosurgeon but he was pretty positive," McKendry says. "All I could think about was getting back on the field."
Many preached caution. Former Penrith prop John Farragher became a paraplegic after a scrum collapse in 1978 and there's also the recent case of Alex McKinnon.
Others have made it back, including Ben Ross (who returned after two years on the sidelines) and former Penrith and Queensland forward Craig Greenhill.
"There were periods there where we were unsure how the future was going to be," coach Ivan Cleary told the Daily Telegraph last year. "[But] you wouldn't get any tougher. He never doubted he'd be back."
McKendry made his comeback late last season and his confidence quickly returned. "Out there, you can't really think about it," he says. "You can't hesitate. You just have to get stuck in."
He was immense last week, carrying for 160m and bending the Roosters line at will.
It's the kind of form that has put him in the frame for a Kiwis recall next month. There's plenty of competition but McKendry has a decent shot of adding to his eight international caps.
"Obviously it would be great to get back in but I have to keep doing the job for Penrith," he says. "That has to be the focus at the moment."
