After arguably having the best festive period of any team in the Premier League, Tottenham slipped back into their inconsistent malaise by slumping to a 2-1 defeat to Crystal Palace at the weekend.

After beating current league leaders Chelsea 5-3 on New Year’s Day and dominating first-half affairs at Selhurst Park, Spurs took the lead early in the second 45 through the prolific Harry Kane.

At this point, a team with realistic ambitions of finishing in the top four and with a squad that cost countless millions of pounds to comprise should have been able to ride out the hosts’ resurgence.

Unforgivable inability to keep the ball, dropping deep immediately after taking the lead, the concession of needless free-kicks in their own half and being unable to deal with the growing threat of Jason Puncheon down Palace’s right played their part in Spurs’ disappointing collapse.

However, a perhaps unforeseen factor also played its part in Tottenham’s inability to see out the game; the absence of young central midfield duo Ryan Mason and Nabil Bentaleb.

The pair, 23 and 20 respectively, are graduates of the Spurs youth academy and have only amassed a total of 41 Premier League appearances between them – but they were sorely missed.

Bentaleb will continue to be absent from Spurs duties for the time being as he is away with Algeria at the African Cup of Nations, while Mason picked up a hamstring strain in the win over Chelsea.

In their place Mousa Dembélé and Benjamin Stambouli occupied the two central midfield roles and given the collective cost of roughly £20 million to bring them to North London, surely should have had the quality to dominate affairs in the Selhurst Park boiler room.

They didn’t.

Dembélé in particular has come in for criticism from the Tottenham faithful following the defeat, with his role in the squad continuing to be a point of contention.

There is no doubting the Belgian’s ability on the ball and skill; when he is on form and used in a forward-thinking role he looks like a real threat to the opposition.

However, when operating in the heart of midfield, the problems that Dembélé brings to proceedings outweigh his virtues.

Last season the former Fulham man was consistently guilty of coughing up possession in his own half when he was used in central midfield and always tried to do much on the ball.

Although this seemingly has been stamped out of his game or at least is less frequent, Dembélé’s distribution against Palace predominantly consisted of passes backwards or sideways.

In Mauricio Pochettino’s 4-2-3-1 formation, Christian Eriksen rightly commands the role behind Harry Kane. It is a position that Dembélé could well play but his chances to operate there will be few and far between.

As such, and with the Belgian lacking the pace to operate from wide, just how and if Spurs will use this frustrating figure in the short-to-medium term remains to be seen.

Stambouli was brought to White Hart Lane from Montpellier in the summer but has yet to be given a run in the team to show what he is fully capable of.

Against Palace the 24-year-old showed some nice touches on the ball and got himself out of a number of tight situations through clever footwork and deft movement.

The problem is that those situations were largely of his own making and when he did have time to lift his head up and pick a pass Stambouli gave the ball away on more occasions than not.

His tackle to receive a yellow card was completely pointless, while his concession of the penalty that got Palace back in the game, whether it was a foul or not, was again completely unnecessary.

Stambouli’s battling qualities, neat technique and work-rate show that Spurs have a player that can improve once he gets to grip with the English game but for the time being he looks like more of a back-up to the young pair than a player that can command a place in the team every week.

In the end, the introduction of Adlène Guedioura from the Palace bench at half-time was decisive; neither Stambouli or Dembélé could shackle the substitute, who provided the impetus for the home side’s comeback.

What Spurs missed against Palace were the attributes that Bentaleb and Mason bring as a pairing.

The Algeria international’s positional discipline would have stamped out the pockets of space that started to appear in front of the Spurs back four in the second 45.

His careful consideration when picking passes would have meant that Spurs would have kept the ball in the second half when they needed to most, rather than simply giving it straight back to the opposition.

Mason’s energy and off-the-ball running would have provided something different in Tottenham’s attempts to break down a stubborn Palace side and would have offered an additional player able to get beyond Kane in attack.

The pair’s collective work-rate, drive and will-to-win was not replicated by their replacements and Spurs came out second best as a result.

A year ago most Spurs fans could not have dreamed of a situation where they would be reading this article and the two youth products would have as much influence over the team.

Ironically, with the considerable expenditure on new overseas players by Tottenham in recent transfer windows, along with Harry Kane, two of their most ‘valuable’ and important stars are now youngsters who have flourished in and graduated from the youth ranks at little expense.