The problem with relying heavily on a group of key players is working out what to do when some are not around.

Next season, Tottenham will be expected to challenge for the title and hold their own in the Champions League. To do so, they will require more than just 14 or 15 footballers who have the complete trust of Mauricio Pochettino. Tottenham probably need about 20 men who can slot in at any time, with little discernible difference to the quality of the team.

Anyone who has watched Spurs regularly can name Pochettino’s preferred XI. Within his squad, a mere 13 have started more than 10 League games. Such consistency of selection has clear benefits, yet what happens to those who have to settle for the odd substitute appearance?

Those players need to know that, if they train well, they have a chance of starting the biggest matches, even if all their colleagues are fit. If they suspect the coach will always rely on the same men, their level of intensity in training may drop and when called upon, it is then difficult to perform to their full potential.

On March 17, Borussia Dortmund arrived at the Lane, won 2-1 and completed a 5-1 aggregate victory to send Tottenham out of the Europa League. Spurs were left with a single objective: the Premier League title. Pochettino’s response was perfectly understandable. With such a prize to chase, virtually every manager would try to choose his strongest XI every week. In the six games since Dortmund, he has started with just 14 different players. Only one of those changes - Jan Vertonghen for Kevin Wimmer - involved omitting a player who was healthy and available. Heung-Min Son- who opened the scoring yesterday - replaced the injured Erik Lamela for the 1-1 draw at Liverpool and stepped in at Chelsea last week when Dele Alli began a ban.

Ryan Mason replaced the suspended Mousa Dembele against Southampton yesterday.

Some coaches tweak their selections based on the strengths or weaknesses of the opposition. Others stick largely to the same men and the same principles, believing that if their players carry out their instructions, they will win. Pochettino belongs to the latter camp.

Tottenham vs Southampton: Player Ratings 12 show all Tottenham vs Southampton: Player Ratings 1/12 Player Ratings? Who impressed at the Lane? 2/12 Hugo Lloris: 5 The Frenchman had little to do throughout the game but was at fault for Steven Davis' equaliser on the half-hour mark and will be disappointed with himself. 3/12 Kyle Walker: 5 Although Dusan Tadic proved to be a little workshy in regards to tracking back Walker rarely got the better of the Serbian midfielder, who was a constant threat. 4/12 Toby Alderweireld: 6 Caught out by Shane Long's pace on a couple of occasions and did not cut the composed figure which has earned him so many plaudits this season. 5/12 Jan Vertonghen: 6 Stepped out from defence confidently whenever the opportunity arose but, like Alderweireld, struggled to cope with Shane Long's speed. 6/12 Danny Rose: 6 The full back was charged with stifling an in-form Sadio Mane and won his individual duel. Far from flawless, but refused to give up on a number of lost causes and bombed up and down the flank in searing heat. 7/12 Eric Dier: 6 The midfielder did not look as assured without Mousa Dembele alongside him and was bypassed by Davis far too easily for the Northern Irishman's second goal. 8/12 Ryan Mason: 5 Started well enough but when Southampton began to turn the screw the game passed the midfielder by. Simply unable to fill Dele Alli's shoes. Julian Finney/Getty Images 9/12 Erik Lamela: 6 Involved in plenty of nice interchanges and claimed an assist for the goal, even if his pass did not appear to be intentionally aimed at Heung-min Son. 10/12 Christian Eriksen: 6 Missed an early chance, which ended up epitomising his entire performance. Encouraging in glimpses but, overall, lacking a cutting edge. 11/12 Heung-min Son: 7 Tottenham's best players. The South Korean scored his fourth goal of the season with an accomplished finish when he refused to give up on what was a lost cause and got his just rewards. A real livewire but eventually ran out of steam and was withdrawn. 12/12 Harry Kane: 6 Not the striker's best afternoon. He did not fashion many chances and spurned the ones which fell his way, the most notable of which was an effort on the stroke of half time when it appeared easier to pass to Erik Lamela rather than go it alone. 1/12 Player Ratings? Who impressed at the Lane? 2/12 Hugo Lloris: 5 The Frenchman had little to do throughout the game but was at fault for Steven Davis' equaliser on the half-hour mark and will be disappointed with himself. 3/12 Kyle Walker: 5 Although Dusan Tadic proved to be a little workshy in regards to tracking back Walker rarely got the better of the Serbian midfielder, who was a constant threat. 4/12 Toby Alderweireld: 6 Caught out by Shane Long's pace on a couple of occasions and did not cut the composed figure which has earned him so many plaudits this season. 5/12 Jan Vertonghen: 6 Stepped out from defence confidently whenever the opportunity arose but, like Alderweireld, struggled to cope with Shane Long's speed. 6/12 Danny Rose: 6 The full back was charged with stifling an in-form Sadio Mane and won his individual duel. Far from flawless, but refused to give up on a number of lost causes and bombed up and down the flank in searing heat. 7/12 Eric Dier: 6 The midfielder did not look as assured without Mousa Dembele alongside him and was bypassed by Davis far too easily for the Northern Irishman's second goal. 8/12 Ryan Mason: 5 Started well enough but when Southampton began to turn the screw the game passed the midfielder by. Simply unable to fill Dele Alli's shoes. Julian Finney/Getty Images 9/12 Erik Lamela: 6 Involved in plenty of nice interchanges and claimed an assist for the goal, even if his pass did not appear to be intentionally aimed at Heung-min Son. 10/12 Christian Eriksen: 6 Missed an early chance, which ended up epitomising his entire performance. Encouraging in glimpses but, overall, lacking a cutting edge. 11/12 Heung-min Son: 7 Tottenham's best players. The South Korean scored his fourth goal of the season with an accomplished finish when he refused to give up on what was a lost cause and got his just rewards. A real livewire but eventually ran out of steam and was withdrawn. 12/12 Harry Kane: 6 Not the striker's best afternoon. He did not fashion many chances and spurned the ones which fell his way, the most notable of which was an effort on the stroke of half time when it appeared easier to pass to Erik Lamela rather than go it alone.

His mentor, the idiosyncratic Argentine Marcelo Bielsa, is said to believe that if football were played by robots, his teams would always win. You could imagine Pochettino saying exactly the same in private. Indeed, his decision to play a back-three in the 2-1 win at Watford in December was a rare example of adjusting tactics according to the opponent.

When asked about his objectives for next season, Pochettino spoke not about signing new players but about improving those he has. His aim is not to develop different plans for certain matches but to make his principal plan even better.

“To create and maintain our way of playing, we need to build our own ideas and philosophy and hopefully the consequence of that is to finish above all our opponents,” he said. “We are clear about the areas we need to improve and how but that doesn’t mean we need to add players. The players we have need to make progress and do better - tactically, mentally and in other areas. But the most important thing is we know how.”

Tottenham are already assured of their highest finish in the Premier League and will secure second place - ahead of Arsenal - if they collect at least a point at Newcastle on Sunday.

Southampton boss Ronald Koeman called Spurs the best team in the League, after Steven Davis’s two goals had brought the visitors victory. With a Champions League campaign to come, and a new stadium they hope will be ready in summer 2018, Spurs have plenty to look forward to.

But make no mistake - more teams will be wise to their style next season. To maintain the current rate of progress, Pochettino might decide he needs to be a little more flexible.

