The match was suspended shortly before half-time for more than twenty minutes as the supporter received medical attention in the stands before being stabilised and taken to hospital.
The incident occurred in the East Stand, along the side of the field where left-back Reguilon had been playing, and it was the Spaniard who alerted referee Andre Marriner to the distressing scene as Spurs were waiting to take a corner.
A defribrilator was rushed across the pitch from the dugout as the match was first paused and then formally suspended, with both sets of players returning to the dressing rooms while the fan was treated.
“We heard the fans screaming,” Reguilon told Sky Sports. “I saw one guy lying down and I went to the referee and said ‘we have to stop, we cannot play like this’.
“Now, I think he is okay? That is more important than anything.”
Spurs had been leading 2-1 at that point and went on to win 3-2 to spoil Newcastle’s party on the day they welcomed their new Saudi Arabian owners to the club.
Kane was among the scorers as he found the net in the league for the first time this season, but his first thoughts post-match were with the stricken fan.
“First and foremost we want to say best wishes to the guy in the stands,” he said.
“It was not a good sight to see. It was devastating to see. It wasn’t nice for the fans to see that. But we hear, he is stable so we are thankful.”