GUTTED Celtic star Partick Roberts described his side's thrashing by Barcelona as embarrassing and admitted they were played off the park at the Nou Camp.

The winger, who said the 7-0 defeat was the toughest experience of his career, felt the biggest problem lay with a lack of confidence shown by his team-mates when coming up against world-class performers.

The on-loan Manchester City man - whose parent club come to Glasgow in a fortnight - hoped that Celtic would perform more to their normal standard for the next five Champions League group matches.

Read more: Celtic's players don't try to hide from how they feel about their night to forget in BarcelonaGlasgow Times:

Roberts said: “Going to the Nou Camp is probably one of the hardest things you will ever have to do as a footballer.

“They completely played us off the park. Seven goals, for me personally, is embarrassing. In football, you don’t want to ever get beat. Losing seven goals is always going to hurt but we will get on with it and go again.

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“We deserved to get to the Champions League. We earned that. But we didn’t do it in Barcelona.

“Obviously it is the first game and I don’t know if people were a bit nervous. Coming to the Nou Camp for the first game is very tough. But we have to be more confident than that.

“Me personally, I always try to be confident and I always try to show no fear when I get the ball. As an XI, we have to be the same and play the ball as we usually do on a weekend.

“We have to come to places like this and try to play football. I know it is hard, but it has got to be done.

"We have a good togetherness in the squad but this was one night when Barcelona showed how good they truly are. They played us off the park.”

Celtic’s first home match of the group stages is going to be a huge night for Roberts who will not only be out to get some points on the board for the club he currently play for, but also will be seeking to catch the eye of City boss Pep Guardiola.

Roberts said: "I am always looking to show that I can mix it with the best. I always try and do that for Celtic and myself.

"I will go into the City game in the same way, being positive. Hopefully, we can perform better than we did in Barcelona.

"City is a very big club with a lot of staff. There are people there who I keep in contact with and who are looking out for me. They give me feedback and will be at the games, whether it is up in Glasgow or out in Barcelona.

"They text and call me to keep in touch. But while I am at Celtic I am a Celtic player and I will do everything I can to help this club.

Read more: Celtic's players don't try to hide from how they feel about their night to forget in Barcelona

"I haven’t spoken to Pep Guardiola. As I say, my main thing just now is Celtic and trying to prove myself here. He does what he does with the team and I will speak to him at the end of the season. For now, I am focused on Celtic.”

If Celtic are to have any chance of finishing even third, which would guarantee Europa League football after Christmas, then they need to get at least a draw against a Manchester City side who this season have looked a much improved outfit under one of the great coaches of world football.

Roberts said: “City are the same as us in the sense they have a new manager and a new belief in a system and a style of play.

"They will be another tough side. We all know that Guardiola used to coach at Barcelona and taught most of the players we faced at the Nou Camp.

"It will be very hard, but I am up for any challenge. It’s at Celtic Park, which can help us, and hopefully we can put on a good performance for our home support.”