FRANCE Under-21 manager Sylvain Ripoll believes both Moussa Dembele and Olivier Ntcham are capable of becoming top European players in future – thanks to the influence of Celtic manager Brendan Rodgers.

The Parkhead club have enjoyed enormous success both on and off the park in recent years by identifying overseas players with raw talent, giving them first team experience at domestic and European level and then selling them on.

The Scottish champions have made multi-million pound profits on the likes Ki Sung-Yueng, Victor Wanyama and Virgil van Dijk in the past decade as a result of their shrewd recruitment policy.

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Their most successful bit of business to date has been the sale of Dutch centre half Van Dijk - they bought him from Groningen for £2.6 million in 2013 and then sold him to Southampton for £13 million in 2015.

And they have just banked a further £7.5 million from the sell-on clause they insisted on when he moved to the St. Mary's Stadium two and a half years ago.

The 26-year-old became the world's most expensive defender when he was transferred from Southampton to their Barclays Premier League rivals Liverpool for £75 million at the start of this month.

Ripoll, the former Rennes, Le Mans and Lorient player and Lorient manager, has no doubt that both Dembele and Ntcham, who cost £500,000 and £4.5 million respectively, can win lucrative moves to big clubs in larger leagues in future if they continue to work under Rodgers.

He revealed he is a huge admirer of the former Swansea City and Liverpool manager and predicted his players can realise their vast potential as a result of working under the Northern Irishman in Scotland.

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He said: “I was very pleased when Olivier signed for Celtic because I think it’s a very good club for him - and I also thought it was a very good idea for Celtic to sign him because he is a great player. Olivier is important for the collective of the team. He always thinks to the team and has a good technique as well.

“Brendan Rodgers is a very, very good manager. I don’t know him personally, but I obviously know the work he has done at the clubs he has been at in his career, at Swansea City, at Liverpool and at Celtic.

“I have a big respect for Brendan Rodgers and how his teams play football. Moussa and Olivier both work with a good manager and that is good for their development.

“I think both Moussa and Olivier also have the potential to go on and do very well in the game in the future. But they have to have the right mentality and they have to work all the time."

Dembele has been repeatedly linked with some big money moves to some of England's top flight clubs and Brighton are rumoured to be preparing to table a £20 million bid for him before the January transfer window shuts.

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“I understand that Brendan Rodgers wants to keep his player," said Ripoll. "If I was him I would think the same. But I don’t know what is going to happen. Perhaps he (Dembele) will go to a very, very big club. But Celtic is a very big club for him to play at and score goals at.”

Ripoll has travelled to Glasgow to watch Dembele and Ntcham in action for Celtic twice this season – in the Champions League qualifier against Rosenborg in July and then in their Group B meeting with Anderlecht last month.

He believes that having his players, who have won all five of their European Under-21 Championship qualifying matches so far, involved in continental competition with their clubs is hugely beneficial to his own side.

“Having players who play in the Europa League and the Champions League is certainly good for us,” he said. “The more games they can play at a high level the more good experience they can get. That helps the France Under-21 team when they play. They can use the experience they get.

“Moussa and Olivier are very important to the national team selection because they are players who play with a big club and who are used to playing in big matches. I think that is important.

“I have gone to Glasgow to see Moussa and Olivier play twice this season. I came for the Champions League qualifying game against Rosenborg and the Anderlecht game in the group stages.

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“Olivier came on in the middle of the Anderletcht game. For me, he changed the game. Celtic were much better. Olivier plays for the team, thinks for the team, is very important for the team.”

Both Dembele and Ntcham, the central midfielder who was signed from Manchester City for a £4.5 million transfer fee during the summer, have experienced mixed fortunes during recent months.

Ntcham has been exceptional in many games, most notably the Champions League play-off matches against Astana back in August, but he has failed to perform as well in other outings.

Ripoll, though, believes that is due to the duo’s youth and inexperience and he is confident their consistency will improve with time as they make more appearances for the Glasgow club.

“It is difficult to play at this level,” he said. “It’s logical for young players to have some good games and some not so good games to begin with. It is difficult to progress. They have to play regularly and work hard.”