The England international has blossomed into one of the Premier League’s most-exciting players over the past 18 months following his move to Tottenham from MK Dons in a £5m deal in 2015.
Alli was named the PFA young player of the year in 2016 after the attacking midfielder scored 10 times in 33 games in his first season in the Premier League under Mauricio Pochettino.
The 20-year-old has rediscovered his best form in recent months after a return of five goals in his last three Premier League games to help hoist Tottenham up to third place.
Alli scored either side of half-time to help Tottenham ease to a 2-0 win against Premier League leaders Chelsea last week and end the west London side’s 13-game winning run in the top flight.
Writing in his Daily Mirror column, Collymore had a warning for Tottenham about Alli.
“Don’t get me wrong, I’d love for his education to be completed at Spurs, if they are cutting a swathe through European competitions,” Collymore said.
“But, if, two years from today, they aren’t making a dent in the Champions League and aren’t buying the sort of players who can help him achieve his aims, then I would genuinely look at going abroad.
“He could play for Bayern, Barca or Real tomorrow, and they would hone his skills.”
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