Harper, Victoria's talented young wicketkeeper, was behind the stumps when accidentally struck on the helmet by Jake Lehmann's bat.

The freak accident ensured the push for concussion substitutes in first-class cricket gathered serious momentum in Australia, while Harper endured "the worst three weeks" of his life.

The 23-year-old, who made a steady recovery and remains one of Victoria's brightest prospects, has revealed just how serious the setback was.

"It's certainly a time of my life I will never forget and for all the wrong reasons," Harper said on The Athlete Diaries podcast.

"The next three weeks were very lonely ... I was just feeling horrendous.

"I was literally in a dark room for three weeks and didn't even know when the sun had risen and when the sun was setting.

"I'd get woken up every hour to get my heart rate and stuff checked, to make sure I was still conscious. I was having these faint attacks, where I'd pretty much pass out for a minute.

"I wasn't allowed to leave my hospital bed, even to go to the bathroom."

Harper recalled how physios taught him how to walk again, and how looking at any screen or trying to read would trigger intense headaches and dizziness.

"It was really frustrating ... I was almost embarrassed," he said.

"Something in the back of your brain sends signals to the legs.

"These signals weren't as clear as they should've been."

Cricket's concussion policies have come along in leaps and bounds over the past five years.

Harper suggested it was important the issue is treated seriously, but also that juniors know that every head knock will not result in concussion.

"You actually can get hit and just get straight back up from it. You'll know when you've got a concussion," he said.

The youngster was ruled out of the final stages of the most recent Big Bash League because of another freak concussion, but returned later in the season and finds many blows to the helmet oddly reassuring.

"The things that have helped the most in the past few years have been when I've been hit and fine," he said.

"I know what sets me off ... every time I get hit in the head by a fly I'm not going to get concussed."

Australian Associated Press