Brendan Rodgers said his Celtic side weren't at their best in their 5-0 defeat to Paris Saint-Germain but paid tribute to opponents he said were "world class".

The opening Champions League group stage game saw Celtic fall to their heaviest home European defeat at the hands of an expensively-assembled PSG side, with Neymar Kylian Mbappe and Edinson Cavani all on the scoresheet.

Rodgers said that the quality of team his players were up against couldn't be disputed but that he felt Celtic hadn't matched the standard he expected in the first half.

"We were clearly well beaten and it's the top level in world football we've seen tonight," he said. "I'm still really disappointed with the first half.

"That wasn't what we had spoken about and what we'd anticipated.

"We were too passive in the first half. Second half we were much better and of course you can still concede to that level but I felt much better, especially in that first 30 minutes [of the second half].

"Our pressing and our aggression and we were much more competitive. They still scored two goals in that period but you have to tip your hat to them.

"They're a top class side full of world class players and we saw their qualities tonight."

PSG are targeting major success in the competition, with the recruitment of Neymar and Mbappe a statement of intent. Rodgers said there was no mistaking the threat they would pose to any side.

"That's how they've been playing in their domestic league," he said. "The qualities, the goals, they've just got threats all over the field.

"They have top class performers and they have that confidence and experience.

"You've got guys there with Champions League winners medals and they know how to control games like that."

Celtic's last Champions League campaign started with heavy defeat to Barcelona and Rodgers was hoping there would be another lift in performance levels following the PSG defeat. He said there had to be perspective about the team's aims for the competition and that the players would be learning as the group progresses.

"It'll be the same," he said. "I'm just disappointed that we couldn't be better in that first half.

"We had spoken about it. It was too passive and not aggressive enough but like I say, this competition is a great learning experience for us. Playing against that level, the players will be better for it.

"Of course, our bigger picture in this competition is really to be in European football after Christmas so we can't forget about that. We look forward to our next game against Anderlecht and in between times we've got important league games and cup games as well."