Madrid, Sep 11 (IANS): FC Barcelona kick off their Champions League campaign with their toughest challenge of the season to date when last year's beaten finalists, Juventus visit the Camp Nou here on Tuesday.

Juventus may have lost last season's final 1-4 to Real Madrid, but they claimed Barcelona's scalp along the way, beating the Catalan's 3-0 in Turin and holding on for a 0-0 draw in Camp Nou.

Barca will welcome the Italian Champions as joint leaders in the Liga Santander after a 5-0 thrashing of local rival Espanyol on Saturday night kept intact their 100 percent league record, but this game will be a stern test of their credentials.

Leo Messi has had a flying start to the season and has already scored five goals, while Luis Suarez is also fully fit after missing the start of the campaign with an ankle injury.

Meanwhile record signing Ousmane Dembele made his debut on Saturday and it will be interesting to see if Barca coach Ernesto Valverde puts him in the starting 11 on Tuesday or whether he keeps faith in Gerard Deulofeu, who has offered pace and enthusiasm in this start to the campaign.

Valverde has brought stability back to Barca and apart from the nine goals they have scored at the start of the campaign, he will be just as happy with the three clean sheets his side have kept.

As a result it is hard to see him making too many changes to the Barca defence, especially as Sergi Roberto is still not fully fit to challenge Nelson Semedo at right back.

Juventus are in a similar situation in Italy, where the side coached by Massimo Allegri too have won their three opening games of the season, scoring 10 goals and conceding just two.

Last season saw them shut Barca out in Camp Nou and a draw would be another good result to kick off the European campaign of two sides whose aim is to make it all the way to Kiev for the World Cup in May.