Once again it proved impossible to keep Cristiano Ronaldo out of the Champions League spotlight as he made his debut in the competition for Juventus on Wednesday.

This time it was not the 33-year-old's goalscoring exploits that stole the show, however, but the red card he received in the 29th minute against Valencia at the Mestalla.

It did not matter in the end as Juventus displayed customary grit to win their Group H opener 2-0 thanks to a couple of penalties tucked away either side of halftime by Miralem Pjanic.

But the sight of the competition's record goalscorer and five-times winner walking off with tears in his eyes will be the abiding memory of his first European night in Juve colours.

It looked a harsh decision as German referee Felix Brych reached for his red card after Ronaldo's seemingly innocuous tangle with Valencia defender Jeison Murillo in the area as Juve launched an attack down the left.

Cristiano Ronaldo
Ronaldo was shown a red card in his first Champions League outing with Juventus on Wednesday.Julian Finney/Getty Images

Ronaldo, signed from Real Madrid for 100 million euros ($117 million) in July, had never been sent off in his previous 153 appearances in Europe's blue riband tournament and even Valencia coach Marcelino appeared to sympathise with the Portuguese great as he walked off in a state of shock.

While lesser teams might have crumbled, playing with 10 men for more than an hour showed just what Juventus are all about.

Manchester City stunned at home

Manchester City
Manchester City were stunned in their Champions League 2018/19 opener on Wednesday.Julian Finney/Getty Images

Manchester City looked far from potential Champions League winners as they fell to a surprise 2-1 loss at home to Olympique Lyonnais on Wednesday with a flat performance leaving them with plenty of work to do to progress from Group F.

The Premier League champions, favourites with some bookmakers to win Europe's top club competition this season, were well below their best throughout and now face a serious challenge to progress from a group which also features Germany's Hoffenheim and Ukraine's Shakhtar Donetsk.

City manager Pep Guardiola, serving a suspension, was forced to watch the game from the stands as his assistant Mikel Arteta took charge and it was a frustrating night for the pair, whose side have now lost four games in a row in the Champions League.

In contrast to a flat-looking City, Bruno Genesio's Lyon delivered a tactically superb display, defending in numbers to nullify City's normally dangerous forward line and then counter-attacking at pace.

Captain Pogba shines for Manchester United

Paul Pogba
File photo of Manchester United star Paul Pogba.Christian Kaspar-Bartke/Getty Images

Captain Paul Pogba produced an outstanding performance garnished by two goals to help Manchester United to a resounding 3-0 win at Swiss debutants Young Boys Bern in their Champions League Group H opener on Wednesday.

Pogba bossed midfield on the artificial pitch and fired United ahead in the 35th minute with a goal of the highest quality, drilling a left-foot shot into the top corner from the edge of the penalty area after side-stepping his marker.

The France World Cup winner made it 2-0 with a contentious 44th-minute penalty, harshly awarded by German referee Deniz Aytekin after Luke Shaw's cross struck Kevin Mbabu's arm as the defender tried to avoid contact.

A darting run by Pogba midway through the second half released Anthony Martial and the forward scored with a clinical finish from eight metres after his compatriot's good work left him with time and space to find the back of the net.

Roared on by a vocal home crowd, Young Boys charged at United in the opening 30 minutes, forcing two saves by David De Gea as the Spain goalkeeper kept out long-range efforts from Mohamed Ali Camara and Christian Fassnacht.

United's defence looked vulnerable on either flank to the home team's

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