The experiences that brought him to a World Cup semi-final include being snubbed by a current England team-mate, nutmegging Luka Modric and Euro 2016 heartbreak against Iceland.
Alli, who scored the second goal in England’s 2-0 win quarter-final win over Sweden, says he does not get nervous but agreed that Wednesday night’s clash against Croatia is his grandest stage yet.
An apt time, then, to reflect on his road from the MK Dons youth system to the Luzhniki Stadium.
Asked to name his toughest experience in the lower leagues, the 22-year-old Tottenham midfielder barely missed a beat before answering “Bradford away”.
It was February 2015 and Alli scored in a 2-1 defeat at Valley Parade, but neither that, nor the appearance of England No.1 Jordan Pickford in goal for the Bantams, is lodged in his mind.
“It was a night game, the pitch was horrible,” he said. “It was a horrible game. They were very aggressive and it wasn’t a nice day. Every time I got the ball people would be kicking, swearing.
“There are a lot of different paths you can take to getting to the England senior team.”
Rewind six months from that match and Alli was announcing himself as one to watch with a confident performance in a shock League Cup win for MK Dons over Louis van Gaal’s Manchester United.
The League One side recorded a stunning 4-0 win but Alli was still a wide-eyed teenager, who sought out United striker Danny Welbeck for a souvenir shirt.
The suggestion was politely rebuffed – a fact the pair are now able to laugh about as England colleagues in Russia.
“Me and Danny Welbeck have a joke about it because I asked him for his shirt,” Alli said. “He wouldn’t give it to me. I think he wanted to keep that shirt but he was polite about it. He was really nice. I wasn’t going to give him mine – I just wanted his.”
Come Wednesday it could be Croatia star Modric that Alli will want to swap jerseys with.
The pair will both be key in the battle for midfield supremacy and have previous with each other - including Tottenham’s Champions League win over Real Madrid last November.
Alli had yet to play a competitive game for Spurs when he nutmegged Modric in a 2015 pre-season friendly – earning a cheerful rebuke from his more established opponent.
“I remember it – he said something,” Alli said. “I always enjoy a good nutmeg. I didn’t shout ‘megs’. I have never done that, even in training.”
Asked if a repeat on Wednesday night was on the cards, he said: “Nutmeg him? Hopefully! But I’m not going to focus on that.”
Not all of Alli’s memorable moments are good ones, with the nadir being England’s Euro 2016 exit to Iceland.
Thinking back to a time when a World Cup semi-final must have seemed an implausible prospect, Alli said: “You want the floor to eat you up. You want to hide and not come out of your room. You want to forget about it and lock yourself away. When Gareth came in it was the first time we relived it.
“You don’t want to watch it back but we know how important it was, going into the World Cup, that we had to go back through it to come out stronger.”