The referee-turned-pundit claims that Alli will get a bad reputation if he allows his ego to get the better of him.
Howard Webb has warned Tottenham Hotspur and England midfielder Dele Alli to be careful during his half-time analysis on BT Sport, after the young star was booked for a poor tackle during the Europa League draw with Fiorentina on Thursday night.
The 19-year-old was cautioned for a late lunge on Viola defender Nenad Tomovic and was lucky to remain on the field after appearing to put his foot in on his opponent while Tomovic was down on the floor.
Former World Cup final referee Webb, now a pundit with the broadcaster, suggested that Alli's ego may get him into trouble in his career if he does not settle down.
The 44-year-old told BT Sport after the match: "He's quite a difficult character to handle, Dele Alli. He's got a little bit of an ego.
"He's not afraid to mix it at all, it's partly the way he plays. He's a great talent, of course, but it's something he needs to be careful of a little bit. He's going to get a reputation."
Alli has been one of the revelations of a superb Spurs season so far in 2015-16, scoring seven goals in 34 appearances in all competitions since making his debut for Mauricio Pochettino's side on the opening day of the season.
He has also broken into the England senior squad, winning four caps, but has occasionally drawn criticism for a perceived lack of discipline.
Spurs, who are second in the Premier League table, secure a 1-1 away draw against Fiorentina in the first leg of their Europa League last-32 clash on Thursday night.