The Tottenham midfielder has drawn rave reviews after scoring 16 goals this season and proved a driving force behind Spurs' dogged pursuit of Chelsea at the top of the Premier League.
His scintillating form has alerted a host of clubs across Europe with British media predicting Spurs will face a battle to hang on to their hottest property this summer.
Already his impact is being compared to that of Michael Owen and Wayne Rooney as youngsters, comparisons that will be reinforced by the fact that, in terms of goals and assists, he is outperforming every other under 21-year-old across Europe's top five major leagues.
This season Alli has scored 16 goals and provided five assists (21 goal involvements), according to Opta, which puts him ahead of RB Leipzig's Timo Werner (15, 4, 19), Monaco's Kylian Mbappe (12, 5, 17) and Borussia Dortmund's Ousmane Dembele (6, 9, 15). The much lauded Julian Brandt of Bayer Leverkusen (3, 6, 9) and Borussia Dortmund's Christian Pulisic (3, 5, 8) are well down the table.
When Tottenham manager Mauricio Pochettino was told that, in total, Alli has more Premier League goals and assists (40) than Steven Gerrard, Frank Lampard, Paul Scholes and Cristiano Ronaldo before the age of 21, his response was 'Wow, that's unbelievable, no?'
"He's special," Pochettino told reporters after Spurs' 4-0 destruction of Watford on Saturday, a game in which Alli scored the opener.
"He's a bit different to all the players that play now at his age. He's so experienced. His energy, his character, his quality. I think he is a unique player. He's different to another, it's so difficult to compare to another."
Pochettino has been credited with playing a major part in Alli's rise and, after deploying him in various roles from holding midfielder to attacking midfielder, has settled on a more advanced role this season as a support striker to the equally prolific Harry Kane.
The role suits a player blessed with quick feet and tireless energy and Pochettino is quick to recognise Alli's talent.
"He's a great. First of all a great kid, I think he's a lovely, lovely person. And then he is a great player. And then, he is so young he can improve a lot, he can learn a lot, his potential is massive. But every day he's improving, and every day he gets more mature. He's improving in his skills, but in his character as well."
Alli has a fiery side and was sent off for a bad tackle on Gent's Brecht Dejaegere in the Europa League in February, but Pochettino says all he needs is love to bring out his best side.
"Of course he is young and he needs to improve, but he needs love. To improve, it's not about to punch him or to punish him."
