1. Christian Eriksen steps up again to get another early breakthrough
The big question before the match was how Spurs would cope without their star striker Harry Kane, who scored 15 goals in 13 games before suffering an ankle injury in last weekend’s FA Cup tie against Millwall.
Opening goals tend to be particularly important, and Kane had contributed three of those in five games – against Fulham, Stoke and Everton – so there was a fear that Tottenham might dominate without really hurting their opponents.
However, Christian Eriksen had provided the breakthrough on the other two occasions against Gent and Millwall – and he stepped up again this time, sending an unerring 20-yard drive into the bottom left corner.
It was vaguely reminiscent of Kane’s opener against Everton a fortnight previously – a clinical low strike from outside the box – and it gave the Lilywhites another perfect start.
This was the fifth time in six matches that they had broken the deadlock before the 20-minute mark – and on the other occasion, against Millwall, they still went 1-0 up in the 31st minute.
2. Dele Alli also chips in again to keep his scoring spree going
Spurs had a bit of a wobble around the half-hour mark, losing some of their intensity and focus and almost conceding an equaliser on two occasions, as Manolo Gabbiadini brushed the side netting and Dusan Tadic fired wastefully over the bar from eight yards.
But the home side promptly switched back on and doubled their lead, with Alli winning a penalty from Steven Davies and converting it himself.
The 20-year-old has now scored in each of his last four matches, and his spot-kick gave Spurs a handsome 2-0 lead before half time for the second successive match.
In fact, it was Tottenham’s 11th first-half goal in six matches – a key factor in their recent run of results, which has produced five wins and a draw.
3. Spurs allow Southampton back into the game
Tottenham were in a strong position as they emerged for the second half, knowing their visitors would have to come at them and risk further damage.
Indeed, Spurs had made the most of an identical scenario the previous week, turning their 2-0 half-time lead into a 6-0 rout of Millwall.
This time, however, they allowed their foes back into the game, conceding seven minutes after the interval.
Unusually, it was ex-Saints defender Toby Alderweireld who made the costly mistake, failing to cut out a cross as the ball went under his foot, enabling James Ward-Prowse to finish at close range at the back post.
Spurs had similarly made life unnecessarily difficult for themselves two weeks previously against Everton, seeing a 2-0 lead halved nine minutes from the end and enduring a nervy finish in a game that ultimately ended 3-2.
On this occasion their advantage was reduced rather earlier in the second half, leaving Southampton – who had scored 10 goals in their previous three away matches – plenty of time to complete their comeback and find an equaliser.
It gave the Tottenham fans a far more stressful 40 minutes than they would have been hoping for when they had been sipping their half-time cuppas.
4. Heung-Min Son struggles to provide a focal point and relieve the pressure
The first-half goals from Eriksen and Alli took the focus away from Son, who was the direct replacement for Kane, and eased the pressure on his shoulders. He was not required to find the net today.
However, as the second half drew on, Spurs needed a different quality from their frontman – an ability to hold the ball up, relieve pressure and keep possession further up the pitch.
Son struggled to do so, particularly in the air. It was not entirely his fault – Spurs did not play to his strengths. But when long balls came his way he invariably ran in behind rather than challenging for the header, hoping in vain that his marker would miss a routine header and gift him a clear route to goal.
Pochettino consequently opted to make a change, replacing the South Korean with central midfielder Harry Winks and pushing Alli up front.
However, the move did not have the desired effect. Spurs still struggled to keep possession and poor decision-making or a lack of quality meant the ball kept coming back – so, with five minutes of normal time left, Pochettino turned to Vincent Janssen.
The Dutchman offered a more physical presence along with an injection of energy and, apart from an ill-advised backheel, he gave Spurs what they had been lacking, while also forcing a save from Fraser Forster – although he should probably have crossed to Alli.
Spurs did not miss Kane’s goals today but they did miss his strength and hold-up play – and if the Lilywhites find themselves in a similar situation in the near future, Janssen may well be introduced a little earlier.
5. The Spurs go marching on.
In the end Tottenham got the job done again, securing their fourth consecutive victory – all of them coming at home – and their 13th in a row at the Lane in all competitions.
Pochettino’s side have capitalised fully on Arsenal’s defeat at West Bromwich Albion on Saturday, moving nine points clear of their arch-rivals, albeit having played an extra game.
Spurs also remain seven points ahead of Manchester United, who are now fifth, and have a healthy cushion in the hotly-contested Champions League race.
They go into the international break with plenty of confidence and momentum, still eyeing their first top-two finish in the Premier League era.
There is plenty to look forward to as Pochettino and the supporters take a breather ahead of the big climax.
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