Paris Saint-Germain coach Carlo Ancelotti believes that Real Madrid and Barcelona are the favourites for the Champions League this season.
Both the Spanish giants reached the semi-finals of Europe's premier club competition in 2011-12.
"Two clubs stand out - Barcelona and Real Madrid," he told La Gazzetta dello Sport.
"Barcelona are strong even without [Pep] Guardiola in charge, but they seem less aggressive and slightly less focused in defence now.
"They look more vulnerable than in previous seasons."
Ancelotti added that Manchester City and Zenit St Petersburg could "surprise people".
"Zenit, coached by [Luciano] Spalletti, and Manchester City, coached by [Roberto] Mancini could surprise people, even though City have been drawn in a tough group, with Real Madrid," said the Italian.
PSG have been drawn against Dinamo Zagreb, Dynamo Kiev and Porto in Group A in the Champions League.