The world record breaking transfer sent shockwaves around the footballing world, last summer.
The Brazil worldwide has enjoyed a blistering start to life in the French capital, scoring 20 goals and bagging 14 assists in 20 games in all competitions so far.
"But there are challenges that everyone seeks. At that time, the Italian league was a lot more competitive", added Ronaldo, who won the FIFA World Player of the Year award three times in a stellar career that also included spells at Real Madrid and AC Milan.
Pastore, who contradicted Silva's midweek comments after the Amiens Coupe de la Ligue win, remains in exile after his late return from South America after the winter break.
Neymar will be absent from Unai Emery's Paris Saint-Germain squad for Sunday's trip to Nantes as he receives treatment on an issue with his ribs. Neymar's former side Barcelona secured the signature of Philippe Coutinho as they continue to revamp following the Brazilian's exit.
He threatened to ruin his legacy among Barcelona fans though when he jumped ship for Ligue 1 giants PSG five months ago.
They are determined not to go behind the backs of PSG, and will not pursue a move without the prior knowledge of the Parisian club.