Van Dijk needed emergency surgery during his time at Groningen in 2012, an eye-opening new interview with his former coach has revealed.
"Virgil was ill, but we didn't know the extent," Lukkien told FourFourTwo. "At first we thought he had the flu.
"He was at home for a few days and in lots of pain. He went to the local hospital but they couldn't find anything, so sent him back home again.
"The pain got worse and when his mum travelled to see him, she realised how bad the situation was.
"She took him to another hospital, which turned out to be crucial.
"I was shocked. When he returned to the club, he had changed from a big man into a shrivelled person. Luckily he managed to recover quite quickly."
Van Dijk has spoken about his surgery scare in the past and recalled how he feared the worst at one stage.
"I still remember lying in that bed," he said not long after the incident in 2012. "The only thing I could see were tubes dangling out of me. My body was broken and I couldn't do anything.
"At such a moment, the worst scenarios were whizzing around your head.
"My life was at risk. My mum and I prayed to God and discussed possible scenarios. At some point I had to sign some papers. It was a kind of testament.
"If I died, a part of my money would go to my mum. Of course, nobody wanted to talk about it, but we had to do that.
"It could have been over."