Pep Guardiola could only watch as Manchester City slipped to a surprise 2-1 defeat in their Champions League opener against Lyon.

The City boss was sat in the stands at the Etihad Stadium due to a touchline ban and his side lacked their usual dynamism as they gifted first-half goals to Maxwel Cornet and Nabil Fekir.

Bernardo Silva pulled one back as City rallied after the break but they could not force an equaliser in an underwhelming start to their Group F campaign.

City had been installed as competition favourites but, under the temporary charge of assistant boss Mikel Arteta, they looked anything but as Lyon punished their early mistakes.

It must have made uncomfortable viewing for Guardiola as he sat in a private box with his family, knowing he could do nothing to alter the course of the game.

City did start brightly with Raheem Sterling looking dangerous cutting in from the left. Sterling perhaps should have attempted a volley when an early chance fell to him but he instead took a touch and drove into the side-netting. He fired another shot straight at goalkeeper Anthony Lopes.

Ilkay Gundogan lofted a dangerous cross to the far post but Aymeric Laporte could not turn in.

Jason Denayer, the defender who left City recently after five years at the club without making a senior appearance, blocked another effort from Laporte.

Lyon played on the counter-attack and City contributed to their own downfall as they allowed former Manchester United forward Memphis Depay to break down the left. The Dutchman whipped in a low cross and Cornet – who had a strike disallowed for offside moments earlier – drove in the opener on 26 minutes as Fabian Delph lost his footing.

City initially responded well and Gundogan thought he had netted a quickfire equaliser but Sterling was flagged offside. Gabriel Jesus, starting up front in place of Sergio Aguero, had a penalty appeal turned down after a challenge from another ex-United player, Rafael.

But Lyon pushed for a second and Houssem Aouar and Ferland Mendy had shots blocked. City lost control and were punished for more sloppiness two minutes before the interval as Fernandinho lost possession. Fekir, a recent Liverpool target, broke clear and fired home a low shot.

Jesus attracted some negative comments from the crowd as he swapped shirts with Marcelo at half-time but he attempted to lead the fightback after the break, forcing a save from Lopes.

Fernandinho also shot wide but City remained vulnerable and had a let-off when Depay struck the post.

Arteta decided to introduce Aguero just after the hour but it was Bernardo Silva who revived hopes, squeezing in a shot from Leroy Sane’s cutback.

Substitute Sane proved a handful for the Lyon defence but he missed an opportunity when he failed to make contact on a Riyad Mahrez cross. Aguero shot at Lopes but missed the target with another effort and Sane also sliced wide as time ran out.