Dele Alli's knack for surprises impresses Mauricio Pochettino

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.

Kane, who has 19 league goals this season but faces several weeks out, was hardly missed in the first half particularly as South Korea's Son Heung-min slotted in seamlessly to the sole striker's role in Tottenham's 3-5-2-1 formation.

Tottenham went six games without a win in all competitions earlier in the season when Kane suffered a similar injury.

Pochettino, however, seemed more than satisfied with his back-up strikers on Sunday.

"Sonny did well," he said. "He had some chances to score. His movement was great and he connected with Dele and Christian. I'm very pleased with his performance."

Southampton had their own striking dilemma with Manolo Gabbiadini limping off with a groin injury, although they responded well in the second half and pushed Spurs hard after James Ward-Prowse pulled a goal back.

"Hopefully he will not be out too long," Saints manager Claude Puel said. "It is disappointing, a draw seemed normal for me. It was a strange game, strange first half. We conceded two goals without being under pressure."