Since the Italian took charge, PSG have won six, drawn one and lost none. They remain top of the league, one slender point ahead of Montpellier, and strong favourites for the title, yet it would be wrong to assume that life is all rosy inside the Parc des Princes.

Firstly, the opposition they have faced has not been of the highest order - the visit of Montpellier represents comfortably the biggest test for Ancelotti yet - and secondly, the team is not looking any more fluid or coherent than it was under Antoine Kombouaré.

Montpellier in sparkling form

Montpellier have had tougher fixtures than PSG in 2012 and their record is even more impressive: played seven, won seven, scored 13, conceded none. Understandably, with the arrival of Ancelotti, the media have talked about PSG more than Montpellier in recent weeks, but René Girard's men are the form team in France and I expect them to surprise a few in this weekend's eagerly-anticipated meeting.

Ancelotti needs time to find his strongest team and to get them playing together. He has already tried four different centre-back pairings and does not yet look to have settled on a duo. Mamadou Sakho and Diego Lugano have played together most often, although new signing Alex - who looked rusty on his debut at Nice - now enters the equation. The former AC Milan trainer needs to make the right selection on Sunday because in Olivier Giroud, Montpellier boast the most dangerous and complete striker in Ligue 1.

The strapping target-man has ten goals in his last 12 games and is liable to exploit even the slightest weakness in the PSG backline. He is also likely to get a good service with outstanding Moroccan playmaker Younes Belhanda back from the Africa Cup of Nations and another youth-team product Rémy Cabella starting to show his considerable talent too.

Collective strength

Montpellier may not have millions to spend, but they possess a strong squad of players, many of whom have been together since the club's promotion in 2009. Their harmony and collective strength shines through in virtually every showing, and contrasts with a PSG side that too often resembles a collection of (admittedly gifted) individuals.

How many times does Kévin Gameiro make a good run only for Nenê, Jérémy Menez or Javier Pastore to choose another option? It is something the PSG fans see far too often, although this is nothing new. PSG's attacking quartet struggled to gel under Kombouaré in the first half of the season too, but at least Gameiro knew he was the club's main striker. He no longer seems to sure with Ancelotti, who tried to sign Carlos Tevez and Pato last month and would still like to bring in a world-renowned striker.

Gameiro paying the price

Gameiro is playing like a man whose confidence has been shot to pieces. Rumours that Pastore's return from injury will result in the France forward being dropped (and PSG lining up without a recognised striker as they did against Toulouse) can hardly be helping his self-esteem.

These kinds of problems are inevitable at a club that is trying to transform itself in to a European force overnight. PSG may well become an invincible force under Ancelotti, but they are not there yet.

Upset in the offing

In the meantime, they will struggle against sides that have been together longer and have a stronger team ethic. Montpellier travel to the capital as underdogs in the eyes of many because their names aren't as glamorous as those in the PSG ranks. But don't be surprised if the so-called 'underdogs' prevail and throw this season's title race wide open.

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