The former France international believes that the Paris-based outfit relies too much on its Swedish striker and thinks head coach Carlo Ancelotti is yet to find his best system.
The ex-Chelsea defender and France international has warned the Ligue 1 table-toppers that they will need to find the right balance in the squad in order to challenge for the league title and that the role of attacking midfielder Ezequiel Lavezzi will be key. Ibrahimovic currently leads Ligue 1 with 12 goals through 14 matches.
"They are very dependant on Zlatan Ibrahimovic," Desailly told LeParisian.fr. "Carlo Ancelotti needs to find a system that suits him. When Ezequiel Lavezzi comes into the team it seems that his presence has a big impact on the players and balances the team a bit."
Desailly also discussed the club's current form and the pressure that they face because of their spending power.
"It is not easy for them," Desailly added. "The players must not buckle under the pressure of the fact that everyone expects them to produce great performances every time they play a game."
PSG took the top spot in Ligue 1 on Saturday with the 4-0 thrashing of Troyes, which put the club above second-placed Olympique de Marseille on goal difference.
"The win against Troyes is a massive result, because it was their first in three games in Ligue 1," Desially said. "The confidence they can take from this will allow them to go that little bit further in their next game."
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