BARCELONA — Hansi Flick has rapidly molded a ragged Barcelona into a potent threat to Europe's elite and the visit of his former Bayern Munich side in the Champions League on Wednesday is its first acid test.

The Catalans have not reached the semifinals of the competition since 2019 and were humiliatingly thrashed 8-2 by the German giant in 2020, when Flick was at the helm in Bavaria.

Five-time Champions League winner Barcelona lifted the trophy most recently in 2015 and failing to thrive on the road to this season's Munich final would mark a decade in the doldrums since.

Flick's Barcelona has started La Liga in stunning fashion with nine victories and just one defeat in 10 matches, while scoring 33 goals.

The league leader delivered a stylish display of attacking soccer to rack up a 5-1 win over Sevilla on Sunday ahead of the Bayern Munich clash and Saturday's La Liga Clasico battle against Real Madrid.

Barcelona thrashed Young Boys 5-0 earlier in October in the Champions League after an opening 2-1 defeat at Monaco.

Flick, who led Bayern to a sextuple in 2020, has swiftly transformed a Barcelona side who won nothing last season under Xavi Hernandez into a swashbuckling force despite injuries to several key players.

Gavi made his comeback from a severe knee injury on Sunday, while Frenkie de Jong, Ronald Araujo, Andreas Christensen, Marc-Andre ter Stegen and others face long spells on the sidelines or are only just returning.

Flick's changes

Perhaps the most crucial difference has been former Bayern striker Robert Lewandowski's return to form.

Flick has backed the Polish striker to the hilt despite his struggles last season and the 36-year-old has responded with 14 goals in 12 matches across all competitions.

"Robert is an absolute professional, working hard on his fitness — this body he has, it's not this age," said Flick earlier in the campaign.

" (Scoring) is his job and he is doing this great over years now, not only this year... this is a goal-getter, a striker who scores goals."

Flick has given Raphinha and Lamine Yamal freedom to roam in attack and pushed the team as a whole up the pitch, allowing Lewandowski to spend more time in the area.

The forward is getting more chances than he did for swathes of last season and with his confidence high, he is finishing them off.

However, Flick said his and Lewandowski's Bayern reunion would not just be a battle between the striker and Bayern hitman Harry Kane.

"It's never a battle about players, it's a battle about the (whole) team," said Flick on Sunday.

"Robert scores the goals, that's very important for us (and) he's well connected to the other players — this for me is the way the team has to work."

Flick's Barca seems fitter, with players working hard in training and lasting longer in matches without fading.

"The new fitness coaches are really good for us, we work hard and you notice it in the games," said Pedri in September.

"The team doesn't dip after the 70th or 80th minute, it maintains the same fitness levels."

Barcelona is also pressing with a far greater intensity which helps it out defensively.

"It's very important that not just (the defense) is doing that job, but also other players," said Flick.

"We need pressure on the ball, this is very important."

Raphinha's work-rate has proven essential for Barca and Marc Casado is tireless in midfield and proving a revelation after the club failed to sign a pivot in the summer transfer window.

Barcelona still has limited financial resources and only brought in Dani Olmo, another player who has missed weeks out injured and will be on the bench against Bayern.

With the club's good form the players are in high morale and Flick's Barcelona is ready for its sternest test yet when six-time Champions League winner Bayern Munich visits the Olympic stadium.

AFP