As Mohammed Shami ran in to deliver the hat-trick ball in the final over against Afghanistan, he had MS Dhoni's words in mind. Afghanistan had begun that over needing 16 with three wickets in hand, and were now nine down, needing 12. Only one Indian - Chetan Sharma - had taken a World Cup hat-trick earlier, in 1987. This was Shami's chance to join an elite club. And he did it by nailing a perfect yorker on the base of leg stump. Mujeeb Ur Rahman backed away and swung blindly, only to miss it, and saw the stumps flattened.

"The fewer you have to defend, the more issues you face in executing, but knowing I had Jasprit Bumrah bowling [the 49th over] from the other end was good," Shami said soon after the match. "The hat-trick feels very special, that too getting it in a World Cup is a big deal. Before I bowled the last ball, I had MS Dhoni's advice in my mind. He told me, 'World Cup hat-tricks are rare, just bowl a yorker. This is your chance.' That's what I did."

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It was a moment Shami may have not envisaged a year ago. In June 2018, his central contract was withheld amid allegations of domestic violence by his wife. Then, there was a battle with his own body owing to niggles, even in the aftermath of an ankle surgery that saw him spend nearly a year on the sidelines.

When he finally regained fitness, he had put on a few kilos and even failed the mandatory yo-yo test. His pace dropped and he wasn't on the selectors' radar as far as one-day selection was concerned. There were question marks over his immediate future.

Shami hit the gym and focused on his diet in an effort to reduce weight. Gradually over time, the selectors brought him back into the mix for the ODIs against West Indies at home in October. Since then, there has been no looking back.

In March this year, Shami's improved fitness and work ethic even had Kohli awe-struck. "The way Shami has come back into the white-ball set-up after his Test performances, have never seen him so lean before. He has lost five-six kilos. He's running in and bowling so well," he said at the time. "He's hungry for wickets."

Looking back, Shami reflected on his improved diet as a big factor in his bowling rejuvenation. "This journey towards fitness has taken me two years," he said on Sunday after taking the hat-trick. "I was heavy after the injury, I used to feel tightness in my knee after long spells, so I knew I had to do something extra if I had to play for a longer time.

"I have cut down on my food, I follow a diet and people laugh about it when I tell them that. It's not strict but I avoid stuff doctors tell me to. I don't eat sweets or bread, it has helped me a lot."

On Saturday, his four-wicket haul and his bowling partnership with Bumrah was pivotal in India's 11-run win over Afghanistan that helped them remain unbeaten in the competition.

"I had 16 to defend thanks to your efforts," he told interviewer Bumrah in a chat on BCCI.tv. "I knew it gave me a chance to do something. It was also after a long time that we were bowling in tandem."

The start of Shami's final over seemed nervy as Mohammad Nabi clubbed him to the long-on boundary. Then with 12 to defend off five balls, he first had half-centurion Nabi, whose innings he described as "irritating", hole out to long-on before nailing two perfect yorkers to get rid of Aftab Alam and Mujeeb to seal victory.

"I felt the irritation when Nabi was batting, but we knew if we got him out, the match was ours," Shami said. "He was the only one capable [of winning it in the final over]. We didn't want to show our weakness in the face of his irritation. We just wanted to be aggressive and show intent."

Shami later revealed that bowling short to Afghanistan in the middle-overs had been part of India's plan, one that fetched them the key wickets of Rahmat Shah and Hashmatullah Shahidi, who fell to Bumrah. "It was a much better wicket in the first innings compared to the second," he observed. "The plan was to not bowl too full. They were a little doubtful with the bouncers, so the plan was to mix up our lengths with bouncers."