Alli, who enjoyed a stunning maiden season in the Premier League last year, took his goal tally in all competitions this season to 17 on Sunday when he rolled home a penalty in Tottenham's hard-fought 2-1 win over Southampton which maintained their distant chase of leaders Chelsea.
Fourteen of those goals have come in the league -- four more than he achieved last season.
Alli did not enjoy his best game on Sunday but proved again that he has the handy knack of popping up in dangerous areas in the style of former Chelsea midfielder Frank Lampard.
Pochettino knows that eye for an opening will be vital in the coming weeks while Tottenham's top scorer Harry Kane nurses an ankle injury sustained last week against Millwall.
"Dele always surprises you and you can't guess him," Pochettino, whose second-placed side racked up a 10th successive league win at home, told reporters.
"He has an unbelievable personality and everything's possible with him. It's difficult to sum him up because he likes to run into the box. In the box he looks like a striker because he's very smart and outside the box he plays like a midfielder.
"I saw him at 17 playing for Milton Keynes as a holding midfielder. Maybe one day he will play like a goalkeeper or a centre back or fullback."
Alli's penalty, awarded for a foul on him by Steven Davis, doubled Tottenham's lead after Christian Eriksen fired his side ahead.
Read the full article on eurosport.co.uk: Alli's knack for surprises impresses Pochettino