Iain O'Brien was in the midst of a university project on the not-so-celebrated topic of chlamydia when he had his epiphany.
Each person in the class had to present a discussion on a disease; a colleague chose depression. O'Brien, 37, who played 22 tests for New Zealand from 2005 to 2009, didn't even think depression was a disease. It wasn't until an OHP slide highlighting its symptoms was displayed that a few things started to make sense.
"It sort of explained what was going on," O'Brien said. "It didn't really change anything; it just meant I had a name for it. As a sportsman, you want a name for everything, for every injury."
Still, it wasn't until two years ago that O'Brien was driven to do anything about it. Living in Britain while trying to carve out a post-international county career with Leicestershire, the seam bowler was struggling with injuries - one of the most common precursors to mental health issues - and was quick to temper.
He didn't like the person he was becoming, but even then couldn't make the call, leaving it to his wife to set the ball rolling. After a false start, the O'Briens found a counsellor who could push the right buttons.
"I learned a lot about how I ticked in certain situations. She picked up on some body language; more change of tone and how my words came out, tone and pace. She was genuinely wonderful.
"I always link depression back to something. If you can't see or feel something wrong with your bowling action, you can't change it. As soon as you can start to feel it, you can change it.
"It was the same with [my illness]; as soon as I could feel my mood start to change, I could do something about it."
O'Brien returned to his native Wellington for a comeback of sorts in the 2012-13 season and ended up having what he described as "an episode". It had a positive spinoff.
"I talked to the guys about it and ended up having a couple of guys coming and talking to me. It was nice breaking down those barriers."
Now O'Brien wants the issue up in lights, so to speak. He wants posters in the changing sheds, in the lunch rooms - anything with checklists that young players who might be struggling can identify with and seek help.
"That's important to me. It's not easy dealing with it yourself because you end up being a loner, which I was for the better part of my career."
Like fellow cricketer Lou Vincent, O'Brien said one of his big problems was finding a comfort zone in the team environment. He loved cricket inside the white lines, because it was a form of escapism from social difficulties. But on tour, those difficulties are magnified, sometimes cruelly so.
"Most of what I suffered was social anxiety. I find social situations quite difficult. I'm a lot better now but I still find them uncomfortable," he says.
"On tour, in the hotel bar, going out for dinner, I'd hate that. We were staying at a hotel in Bloemfontein [South Africa] with this nice pool in the middle of the courtyard. Beautiful sunny days, the guys would be out there, someone would have a guitar.
"I'd stay in my room looking down, or I'd go down there, say something stupid, and go back to my room.
"The on-the-field stuff was easy. I didn't have to talk to anybody except the captain. I didn't spend time in the slips so I didn't have to banter.
"Cricket was pretty peaceful for me."