Two teams struggling to impress under respective club legends met in Turin on Wednesday, and without Juventus' star player on show, it was Ronald Koeman's Barcelona who came out on top.

A 34th meeting between Lionel Messi and Cristiano Ronaldo in club football was put on hold due to the latter's latest coronavirus test result, and Andrea Pirlo's side paid the price in a clash that was short of quality.

There were moments. Ousmane Dembele's opener, albeit fortuitous, came at the culmination of a fine run from the winger. On Barca's opposite flank, teenager Pedri shined and Messi showed flashes of brilliance.

At the other end, Alvaro Morata displayed neat finishing, only to see all three of his strikes disallowed, yet Merih Demiral's dreadful second-minute pass ultimately summed up a dismal Juve performance – his late red card compounding the hosts' misery.

Messi netted his 70th group-stage goal to wrap up the victory from the penalty spot, as Barca won in Turin for the first time.

JUVE MISS RONALDO'S EDGE AS MESSI LEADS BARCA

Ronaldo remains in isolation due to what he labelled as "bull****" coronavirus protocols, and without him, the Serie A champions have looked decidedly ordinary.

From the four games Ronaldo has missed since testing positive for COVID-19, Pirlo's team have managed just one win, against Dynamo Kyiv in their Group G opener.

In his 33 club meetings with Messi, Ronaldo has scored 18 goals and provided one assist, creating 19 chances and claiming nine wins.

Though those statistics do not compare favourably to Messi – who has scored 21 times, created 10 goals and crafted 60 opportunities – Juve's reliance on Ronaldo has become clearer in his absence.

Juve have now lost five of the 17 games, across the Serie A and Champions League, Ronaldo has not featured in since the start of the 2018-19 season, winning nine, scoring 26 goals and conceding 17.

With Ronaldo missing, Juve needed Paulo Dybala to step up but, playing in the same central role in a 4-2-3-1 as his opposite number, he went into hiding, having only two shots and failing to create any chances.

The same could not be said of Messi, whose assist for Dembele was his 35th in the Champions League, while the 33-year-old boasted game-highs in key passes (five) – more than any Barca player in any game this season – and shots (four).

KOEMAN FINDS A SPARK AFTER BARTOMEU QUITS

Saturday's Clasico defeat to Real Madrid proved to be the final game of the Josep Maria Bartomeu era at Barca, with the club president – and the entire board of directors – resigning on Tuesday.

Though it was far from a vintage display, and one which might not be good enough against the likes of Liverpool, Manchester City or holders Bayern Munich, Barca did what they needed to in Turin.

Leaving the evergreen Messi to one side, Koeman can also look to impressive displays from Dembele, Pedri and Miralem Pjanic, who made his presence felt against his former club.

Pjanic made 82 passes, second only to Messi, who attempted 95, with the former Juve playmaker achieving an accuracy of 86.6 per cent.

Pedri played with the flare of youth, though he did not shirk off his defensive work – his three tackles the joint-highest in Barca's side, along with Ronald Araujo.

Dembele's display, meanwhile, was perhaps the most promising of all for Koeman. Injury limited the Frenchman to nine appearances last season, and his deflected long-range effort ended a 12-month wait for a goal.

PIRLO STRUGGLING TO FIND A BALANCE

Though it must be noted that Wednesday's clash was only Pirlo's eighth as coach, and his first defeat, Juve looked a shadow of their former selves. 

Dybala may have been anonymous, but he was not helped by Juve's tendency to channel their play down the right flank, with only 25.4 per cent of their attacks going through central areas.

With Pjanic pulling the strings for Barca, Adrien Rabiot and Rodrigo Bentancur failed to combine with any real effect. Ahead of them, Dybala, Federico Chiesa and Dejan Kulusevski combined for just three attempts, with Morata forced into playing both as a poacher and creator – his tally of three opportunities created the most of any Juve player.

In their 200th Champions League game, Juve failed to put any of their 10 efforts on target, albeit Morata had three goals rightly disallowed.

Juve have now failed to score in their last four meetings with Barca, and Pirlo's Bianconeri, with three wins, four draws and a defeat, are a team struggling to discover their identity.