Dele Alli turns 21 on Tuesday. The Tottenham Hotspur star was playing in League One for MK Dons two years ago but Mauricio Pochettino described him as the best young player in Europe this week, while Harry Kane believes he could finish the season as the club's top scorer.

If Alli continues his remarkable trajectory, he will become one of the biggest superstars in world football, helping to fill the void that will one day be left by ageing legends Lionel Messi and Cristiano Ronaldo.

On his 21st birthday, ESPN FC names 21 reasons why Alli will become one of the greats of the game:

1. After his goal in Saturday's 4-0 win against Watford, Alli has been involved in as many Premier League goals (40) before turning 21 as Frank Lampard (15), Steven Gerrard (13) and David Beckham (12) combined.

2. Alli's repertoire of goals is improving. Last season, he scored nine with his right foot and one header. This season, of his 16 goals, four have been scored with his head and four with his left foot. The contrast between Alli's two goals last week -- a poacher's tap-in at Swansea and a brilliant long-range strike against Watford -- was a fine illustration of his variety.

3. Even so, his goal against Watford was his first from outside the box this season -- a sign his confidence is growing. If he can add more goals from distance to his armoury, he will be even harder to stop.

4. Alli is also scoring goals at important times. Of his 19 this season, nine have been the all-important first goal for Spurs, while he has scored decisive late goals against Wycombe Wanderers, Everton and Swansea this year, underlining his emerging status as a clutch player.

5. In May 2016, Alli was named as the Premier League's most marketable player in a survey by SportsPro magazine. His performances this season have further confirmed that, and his key partners already include Adidas and Beats by Dre.

6. Part of Alli's appeal and marketability is his personality. His trademark wave may have got annoying quickly, but the personalised handshakes with his Tottenham teammates are another demonstration of his fun-loving side.

7. Alli lacked a father figure growing up but he has developed a close relationship with Pochettino, and the Spurs manager has described him as "like a son." Pochettino knows when Alli needs praise and when he needs criticism and he has allowed him the freedom to express himself on the pitch. His wonder-goal against Crystal Palace was a good example of that. Alli had options, including a simple square pass, but he felt free enough to do what he did.

8. Alli's partnership with Kane is also special, and is a reason to be optimistic for both Spurs and England fans. Last season, no player assisted another more frequently in the Premier League and this season the pair are playing even closer together, often as a front two.

9. Alli has scored more league goals (16) this season than any other under-21 player in Europe's top five leagues.

10. Alli has signed two new contracts in the last year, the latest tying him to Spurs to 2022, and he is expected to sign another one soon. Given his talent, nationality and Tottenham chairman Daniel Levy's reputation as a driver of a hard bargain, if he does leave the club it will surely be for a world-record fee, surpassing the £89.3 million Manchester United paid for Paul Pogba.

11. Alli was named PFA Young Player of the Year last season and he is a shoo-in to retain the award, and be included on the shortlist for the main prize. The favourite, Eden Hazard, has scored two fewer goals than Alli and has the same number of assists but he is likely to be a champion with Chelsea.

12. Alli's temperament has been rightly questioned after a number of incidents but his response to the first sending off of his career against Gent shows he is made of stern stuff. The moment could be been a downer but Alli has responded by scoring in six of the seven matches since, proving he can overcome setbacks.

13. Alli's record also compares favourably to Ronaldo, who had been involved in 25 goals by the time he was 21, scoring 14 and assisting 11. Only Ryan Giggs comes close to Alli, with 39 goals and assists before he was 21 but the Welshman had played 27 games more.

14. Some of Alli's behaviour suggest he is developing the same single-minded desire for goals as Ronaldo. He berated teammate Son Heung-Min for not passing in the 6-0 win over Millwall last month and remained annoyed even after Son had scored with his next touch. He did the same to Vincent Janssen in the next game.

15. Only Romelu Lukaku (13) and Kane (11) have scored more top-flight goals in 2017 than Alli's 10, level with Bournemouth's Josh King.

16. Part of the reason for Alli's remarkable form this year has been Spurs' switch to a 3-4-2-1 formation, freeing him from defensive duties. He has essentially plays as a second striker in that formation but he remains versatile enough to play wide -- as he did against Watford -- or switch back into a deep midfield role, as he often did at the start of his Spurs career.

17. If Alli stays in the Premier League and continues his trajectory, he is on course to beat Lampard's record of 177 goals from midfield. Lampard admitted recently: "He could break records -- that's why I'm trying to call him a striker! I love his confidence, though."

18. In common with every England player, Alli was subdued at Euro 2016 but his international performances suggest he can be star for country as well as club in the future. He scored with a stunning strike on his debut against France and his dazzling displays in the two friendlies against Germany in the past year have confirmed him as the most exciting player in England's new generation.

19. Alli is not just about moments of individual brilliance -- he is also the most athletic player at Spurs and one of the hardest workers in the league. Against Watford only Christian Eriksen ran further than him -- just -- and no-one completed more sprints. In the previous matches at Burnley and Swansea it was the same story, with only the Dane out-running Alli and no one on the pitch sprinting more. He never needs a rest.

20. Another remarkable thing about Alli is that he is yet to suffer a dip in form. Unlike teammates Eriksen or Dier, who have struggled at times, Alli has more or less maintained his form since the start of the 2015-16 season, despite his youth.

21. And Alli is only going to get better. Pochettino described him as the best young player in Europe this week but the Spurs manager has also said Alli has a lot to learn about football and life. At 21, he is way off his peak.

Source:
courtesy of ESPNFC

by DAN KILPATRICK, TOTTENHAM CORRESPONDENT

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