Fakhar Zaman told the Pakistan physio he didn't think he would be fit to play the night before the Champions Trophy final.
Zaman, who was awarded the Man of the Match award for his aggressive century, pulled out of training on Saturday after feeling unwell. He subsequently vomited several times and, having returned to the team hotel, informed the Pakistan medical staff that he would have to miss the game.
But having been given him medication to settle his stomach - a Pakistan team spokesman suggested Zaman was suffering from a combination of an adverse reaction to something he had eaten and an attack of nerves before the biggest match of his career - Zaman slept soundly and reported himself fit to play at 7am on the morning of the match.
"When we came for practise I wasn't feeling good," Zaman told ESPNcricinfo. "I hit five or 10 balls and said to the coach, 'I don't want to practise today as I'm not feeling well.'
"I went back to the dressing room and told the masseur and physio that I didn't feel good and couldn't work.
"We went back to the hotel and they treated me very well. Our physio, Shane Hayes, was with me the whole night. I said to him, 'I can't play tomorrow,' but he gave me protein and glucose tablets and said 'You will play tomorrow.'
"I woke in the morning feeling good. I sent him a message at 7am saying, 'Thanks, Shane. I'm feeling good.'"
If Zaman was suffering from nerves, it is hardly surprising. He made his ODI debut less than two weeks ago and then found himself in a global tournament final against his side's arch rivals and in front of a TV audience of hundreds of millions.
Certainly in the first few minutes of his innings, those nerves were apparent. He survived an edged catch to MS Dhoni when he had scored just 3 but was reprieved when it transpired Jasprit Bumrah had overstepped.
Gradually, however, he gained in confidence and started to dismantle the India attack
"I'm feeling very lucky," he said. "It worked really well for me. Sometimes you get dropped or survive because of a no-ball but you don't go on and score too many runs.
"At the start they were bowling very well. So I tried to play ball-to-ball. But when I saw there was no swing or movement off the wicket, I started to play my shots."
Meanwhile, Zaman's opening partner Azhar Ali described himself as "the most relieved man" after Virat Kohli fell to a catch at point the ball after Azhar had dropped him at slip off the bowling of Mohammad Amir.
"Dropping him was a really big disappointment," he said. "He's the guy who chases for fun. He's the best in the world. I was the most relieved man when he was out next ball. That sort of batsman never gets out twice in two balls, so it was a blessing form the Almighty. I was very relieved.
"Amir did really well. He is a quality bowler and he can get anyone out. It was so important to get early wickets."

George Dobell is a senior correspondent at ESPNcricinfo