Ask a dozen fans to name the Paris Saint-Germain's best current starting XI and you would almost certainly be looking at 12 different answers. Some would have Kévin Gameiro in attack, others Guillaume Hoarau, some would have both. A few may prefer Mathieu Bodmer in the playmaker role to Javier Pastore. Thiago Motta and Momo Sissoko would feature in most central midfields, although Blaise Matuidi, Bodmer and Clément Chantôme would all get mentions.

As for the defence, there is every chance of seeing 12 different back-fours selected. Carlo Ancelotti certainly seems undecided when it comes to his favourite centre-back pairing.

Diego Lugano and Mamadou Sakho were the Italian's favoured duo at first, before Alex arrived from Chelsea and took the Uruguayan's place. Last weekend at Nancy, to everybody's surprise, Zoumana Camara was asked to brush the cobwebs off his boots to play alongside Milan Bisevac, while the skipper Sakho was dropped.

The fans' responses would surely be even more varied if they were asked which formation PSG should play. Should they go with Ancelotti’s cherished Christmas tree (4-3-2-1), or stick with Antoine Kombouaré’s 4-2-3-1? Or maybe try a 4-4-2, a 4-3-3, or a 4-3-1-2? Ancelotti has experimented with them all.

Since the former Chelsea and AC Milan boss arrived, we have seen some interesting tactical ideas but also relentless chopping and changing. In the recent Bordeaux match, the four-time Champions League winner altered the formation three times. Claudio Ranieri remains the undisputed king but may have found a rival for his 'tinkerman' title.

Results suffering

The bottom line is that three months in to Ancelotti's reign, nobody (including the man himself?) seems to know PSG's best team or most effective formation.

As far as I can tell, the team is not displaying any more cohesion than it showed under Kombouaré, reports of unrest in the camp are becoming more frequent – and, crucially, the results are beginning to suffer.

When Leonardo dismissed Kombouaré in December, PSG were three points clear at the top and well on course for their first title in 18 years. Today they are second, level on points with the leaders Montpellier, who have a better goal difference and a game in hand. The seven points dropped in the last three games have even allowed Lille to clamber back in to the race.

In January, Ancelotti spent €19m on three defensive players (Maxwell, Alex and Motta). This despite the fact the team he inherited boasted the best defensive record in Ligue 1 before Christmas, with only 17 goals conceded in 19 games. In 2012, the stats show that PSG have the league's 16^th best defence and appear to be getting less watertight rather than more (they have conceded 16 goals in their last eight outings).

Statistics never tell the whole story yet PSG supporters are right to start worrying. Time is running out – there are just eight games to play – and a rapid improvement is required; starting with the eagerly-anticipated visit of the arch-rivals Marseille this weekend.

Reports suggest Ancelotti is ready to go back to square one: in other words revert to Kombouaré’s 4-2-3-1, with Nenê, Pastore and Jérémy Menez playing behind a central striker. I would not be surprised if he did. Better solutions have not been found, there is no more time to experiment, and there has probably been too much experimentation already. In the title run-in, PSG need to have a settled starting XI and the players need to have a clear idea of the system and their roles within it.

However famous and successful an manager is, it is never easy to arrive in a new country, take charge of a new set of players in a new league and to produce results immediately. A period of adaptation is required. When Arsène Wenger arrived at Arsenal in 1996, he changed little during the first season, sticking with an experienced back-five and bringing in only two new faces (Patrick Vieira and Rémi Garde). The following summer, once he knew exactly what was required, he made wholesale changes and won the double.

Practicality required

Ancelotti's task is different because he is expected to start winning trophies instantly. Yet a more subtle approach to change might have made the transition smoother.

For example, Camara and Ceara were effectively cast aside by Ancelotti, despite them having been PSG's most consistent defenders in the first half of the season. Maybe Ancelotti doesn't fancy them but was there really a need to alter things so quickly to accommodate Alex? Likewise, Gameiro's confidence has been shot to pieces by reports that Ancelotti does see him as part of the long-term plan. PSG's premier source of goals earlier in the campaign, Gameiro no longer looks like the same player.

Ancelotti is trying to mould his own team. He is introducing his own philosophy and bringing in his own players. In the long run, he may enjoy great success. But if PSG are to win the third league title of their history next month, ideology needs to be placed to one side. Practicality must be the order of the day between now and mid-May.

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