Former Real Madrid midfielder Toni Kroos says Barcelona are not strong enough defensively to win the Champions League.

Barca have won three of their four European games this season with the only defeat coming in a 4-2 reverse at two-time defending champions Paris Saint-Germain on October 20.

They also top La Liga having won 11 of their first 12 fixtures, amassing 48 goals and conceding just 13. They are three points clear of Madrid, although Jose Mourinho’s side did win the season’s first Clasico at Camp Nou.

Hansi Flick has had to mix and match at centre-half this season with the likes of Andreas Christensen, Gerard Martin and Eric Garcia all taking their turn alongside Pau Cubarsi.

Kroos believes that is a fundamental problem for Barca that will be exposed by the better sides as they look to win the Champions League for the first time since 2015.

The ex-Germany international said: “Barça always tries to generate more chances than its opponents, but in the Champions League you find teams capable of scoring several goals in the same game.

“You also face rivals who defend exceptionally well and don’t let you play as you usually do. In those situations you have to know how to defend yourself.”

Bayern Munich have better defensive options than Barcelona – Kroos

Kroos highlighted another of his former clubs, Bayern Munich, as a better bet to land European football’s biggest prize due to the pace and athleticism in their back four.

He added: ”Barcelona don’t have someone like [Bayern’s Dayot] Upamecano, a defender that you can leave completely alone in a one-on-one, with 30 metres of space behind, and have the peace of mind that he will solve the situation.

“With players like Upamecano or [Alphonso] Davies I wouldn’t worry about defending those 30 metres. But with [Joao] Cancelo, Gerard Martín and similar players, it’s much more complicated.”

Cubarsi is Barcelona’s best defender

Kroos, who won the Champions League five times with Madrid and once with Bayern, did reserve words of praise for Cubarsi, who at 19 years of age, is arguably the best young defender in world football.

“He is by far their best defender,” he said. “He has the strength to win individual duels and the speed to face complicated situations. But when I look at the other defenders, I don’t see anyone I would trust.”

Barca return to La Liga action a week on Sunday when Villarreal visit Camp Nou. Their next Champions League game is on November 25 when they visit Azerbaijani minnows Sabah.