Steven Bergwijn has opened up on how his "world collapsed" upon hearing the news his good friend Abdelhak Nouri had suffered permanent brain damage.
Nouri collapsed during a pre-season fixture between Ajax and Werder Bremen in July 2017 and was placed in an induced coma.
The Amsterdam club later announced Nouri, a burgeoning talent in the club's academy, had been diagnosed with "serious and permanent brain damage".
Netherlands winger Bergwijn, who joined Tottenham in January, became big friends with Nouri – known as 'Appie' - in the youth ranks at Ajax before he switched to Eredivisie rivals PSV.
"When I heard Appie had brain damage, I just can't describe my feelings," Bergwijn said.
"At that time I didn't sleep so much. In the first weeks I was scared to play, scared to go on the pitch because Appie was a young boy and out of nowhere.
"It was difficult. It's still difficult. I speak to his brother every day but it's still difficult.
"We were like brothers. I have known Appie all my life, from when we were seven years old. We were in the same squad and since then we are best friends.
"We [PSV] played against RKC and I scored two. I was happy and after the game the team manager came to me and he said this has happened. Yeah, my world collapsed.
"I just waited for the calls from my agent because he went to see Appie. Then I heard two or three weeks later that he had brain damage. I can't describe it. At that time, I didn't sleep so much."
Bergwijn began his Spurs career with a sensational strike against Manchester City in a memorable 2-0 win earlier this month.
The 22-year-old had made a promise to Nouri's brother before making his debut for the Premier League club.
"I spoke with his brother and he told me, 'you're going to score for Appie,' and I said, 'okay, watch me, I'm going to score'. I did it."
Ajax were reportedly interested in bringing Bergwijn back to the club at the beginning of this campaign, but a move failed to materialise and he is now a Spurs player instead.
Bergwijn admits there was little time to think things through in January, saying: "My father called me and said, 'pack your stuff, you're going to London'.
"It was like this. It was fast. I didn't expect to make the transfer now, I thought in the summer. But if Tottenham wants you, you can't say no. It's an honour to be here.
"They have big players. In Holland, everyone regards them as big players, including me. But now they have welcomed me."