Tottenham moved into the Premier League's top four after Harry Kane and Dele Alli scored in quick succession at the end of the first half to secure a 2-0 win at Southampton.
The visitors were fairly insipid for much of the opening 45 minutes at St Mary's but they have plenty of quality and burst into life just before the break, as young England internationals Kane and Alli scored within three minutes of each other.
Mauricio Pochettino's side head into Christmas in fine heart but Southampton find themselves in the midst of a mini-crisis, having now gone five Premier League games without a win.
Saints manager Ronald Koeman had said in the week that the next few matches would be crucial and his side began very brightly.
Sadio Mane was looking particularly lively and he almost gave the hosts an early lead, latching onto a Dusan Tadic pull-back and trying his luck with a low shot which Hugo Lloris did well to keep out.
Mane was soon threatening again but Jan Vertonghen slid across to pull off a good block, and the game settled into a drab period as Spurs took the sting out of the home side.
However, the visitors initially struggled to create much in the way of clear-cut chances, a cross-shot from Christian Eriksen which flew across the goal the closest they came a 40th-minute breakthrough.
Top scorer Kane soon came up trumps, marking his 100th appearance for Spurs with a fine finish for the opener - his 47th goal for the club.
Credit goes to referee Kevin Friend, who waved play on as two Spurs players were poleaxed, and the ball rolled to Kane, who burst past two defenders and then skipped past a Virgil Van Dijk challenge, before calmly placing a shot past Paulo Gazzaniga.
Saints were shell-shocked and conceded a second three minutes later, with their defence again looking disorganised.
The alarm bells began ringing for the home fans when the ball fell to Kyle Walker in acres of space out on the right and he produced a lovely low cross, which gave Alli (43) time to control the ball at the back post before knocking it into the net from close range.
Former Saints boss Mauricio Pochettino was sitting pretty at half-time and the match situation meant his Spurs side were able to cruise through the second period.
Southampton again began the half with the wind in their sails and Graziano Pelle had a shot saved by Lloris before heading wide from Cedric's cross.
Much to the frustration of the home fans, the Saints rarely looked like scoring after that and Koeman will be worried by the lack of chances they created.
Spurs looked lively on the break and Gazzaniga saved from Eriksen and sub Tom Carroll, who could not get enough power on his shot after fine work from Erik Lamela.
There was a moment of concern for Spurs fans when Kane went down with an apparent knee injury late on but he was soon up and about, before being replaced by Heung-Min Son as a precaution.
And a perfect afternoon for Spurs was capped by a clean sheet when Lloris pulled off a stunning save in stoppage-time, stretching out a hand to deny sub James Ward-Prowse, who had got on the end of a Ryan Bertrand cross.
The win was the perfect tonic for Spurs after their defeat at home to Newcastle last weekend and they will next play host to Norwich on Boxing Day, while Southampton will try to arrest their poor run when Arsenal come to St Mary's.
Southampton: Gazzaniga (6), Cedric (6), Fonte (6), Van Dijk (5), Bertrand (6), Clasie (6), S Davis (6), Mane (7), Tadic (6), Wanyama (5), Pelle (6)
Subs used: Ward-Prowse (6), Long (6), Juanmi (6)
Tottenham: Lloris (7), Walker (7), Alderweireld (7), Vertonghen (7), B Davies (7), Lamela (6), Dier (6), Dembele (7), Alli (7), Eriksen (7), Kane (8)
Subs used: Chadli (6), Carroll (6), Son (6)
Man of the match: Harry Kane