Robert Lewandowski scored twice as Barcelona thrashed Young Boys 5-0 on Tuesday, bouncing back from their opening Champions League defeat at Monaco.

Hansi Flick's team were beaten 2-1 by Monaco in their first game in the competition's new-look league phase, but there were no surprises when Young Boys visited Montjuic on matchday two.

Lewandowski gave the hosts the lead in the eighth minute by tapping in a low Raphinha cross, following good combination play between the Brazilian and teenage sensation Lamine Yamal.

After the hosts squandered some decent chances, a quickfire double from Raphinha and Inigo Martinez gave Barca a 3-0 lead, the Brazilian netting a rebound in the 34th minute and Martinez scoring with a towering header less than three minutes later.

Lewandowski got his second and Barca's fourth shortly after half-time, nodding a Martinez corner home from inside the six-yard box, then Young Boys defender Mohamed Camara bundled the ball into his own net while trying to clear Alejandro Balde's cross late on.

Data Debrief: Lewandowski level with Messi

As well as helping Barca to a crucial victory following their matchday one defeat, Lewandowski's double saw him draw level with Lionel Messi as the most ruthless finishers in Champions League history.

He now averages 0.79 goals per 90 minutes in the competition, a figure only matched by Blaugrana great Messi among all players to play a minimum of 50 matches.

Cristiano Ronaldo (0.77 goals per 90), Ruud van Nistelrooy (0.77) and Karim Benzema (0.59) trail Lewandowski and Messi for that metric.

The Poland star has also now scored 51 Champions League goals after turning 30 years old, becoming just the second player to accomplish that feat after Ronaldo (68).

Mauricio Pochettino has defended Conor Gallagher after the midfielder received abuse on social media for failing to high-five a mascot.

Chelsea said in a statement that the “defamatory comments” made towards Gallagher were “completely unacceptable” and that the video had been taken out of context.

The incident occurred in the tunnel immediately ahead of kick-off when the Blues played Burnley at Stamford Bridge on Saturday, with the 24-year-old seemingly not noticing that one of the mascots had held up his hand.

Pochettino rejected any suggestion that the player acted intentionally, and condemned the online reaction to the incident.

“It has upset me so much,” he said. “No one wants to do this with this intention. When you are focusing on playing and starting the game, that sometimes can happen.

“People always try to find things to create a mess. I know Conor. Come on – there’s never that intention. Conor is a great kid and always is caring about everything. I hate how people feel free to abuse on social media.”

It is the second time this season that a Chelsea player has been subjected to abuse on social media, after captain Reece James spoke out earlier this year about unfair criticism he had received when he was ruled out with injury.

Pochettino has spoken out previously about the impact of online attacks against players, and re-emphasised the urgency in ridding the game of the problem.

“Today, abuse of people is so easy,” he said. “Whenever this type of thing happens, we (must not) give too much attention to the type of people that want to create it, to insult and abuse other people. Please stop.

“How is it possible to believe that Conor’s intention is to ignore a mascot? Come on. It makes me very sad.

“Our responsibility is to try to ignore this type of thing. The people that try to create it never help our lives. They don’t deserve attention.

“The problem with social media today is it’s like a compulsory thing if you want to communicate. It measures your value, depending on the followers you have.

“It puts value on you in front of society. That is the problem. We’re seeing too many things like this that are so wrong in society.”

Pochettino also highlighted the example of Barcelona defender Inigo Martinez, who this week was filmed getting out of his car to remonstrate with a fan who had criticised him verbally.

The reaction to Martinez’s handling of the situation has been mixed, with some criticising him for confronting the supporter whilst others have offered their backing.

Pochettino suggested the player had been deliberately provoked in order that his reaction could be filmed and posted online.

“It is society that consumes (this material),” he said. “All that people are interested in are bad things.

“We are a bit responsible also. We opened the door, all the documentaries. People want to see when we are fighting but never things that are good, happy things. They want to find the wrong things. That is the society that we are all involved in.”

Barcelona will aim to close the gap to the top two in LaLiga when they take on neighbours Girona on Sunday.

Barca are not just four points behind big rivals Real Madrid but also their fellow Catalans, who have been the surprise package of the season so far under head coach Michel.

But Xavi’s men go into the clash boosted by last weekend’s 1-0 victory over Atletico Madrid, with Joao Felix scoring the only goal against his parent club.

Xavi told reporters: “It will be a great match. Michel is a great coach and has a philosophy similar to ours. They want the ball and are very dynamic.

“We are looking at the game through several different scenarios because it can play out in different ways. I don’t know which Girona we’ll see, but we’re looking for the win.”

Barca have some injury problems, with Gavi out for the season and now joined on the sidelines by goalkeeper Marc-Andre Ter Stegen and defender Inigo Martinez.

Ter Stegen has sat out the last three games with a lower back problem and has now undergone surgery to correct the issue while Martinez suffered a hamstring injury in the warm-up ahead of the Atletico game.

Fellow defender Ronald Araujo is set to play in a mask after suffering a fractured jaw in an accidental clash with the boot of Atletico’s Marcos Llorente.

“It’s a part of competing,” said Xavi. “Every year we talk about injuries but, yes, we are having bad luck. It’s because of the schedule and the demand it puts on the players.”

Girona have won all but three of their LaLiga matches so far, with their only defeat coming against Real Madrid, and defender Daley Blind insisted all the pressure is on Barcelona.

The former Manchester United and Ajax player told ESPN: “We don’t want to put pressure on ourselves to aim at something. Of course you talk in the dressing room to be as high as possible, that is what you want.

“I think if we continue like this, this already is a special season, but it can be something special as well at the end of the season.

“I think Girona is still a small club which is building, we are in a good build-up now. We take it game by game and the pressure is not on us.

“Barca are a great team, they have some great individual players. It will be a very difficult game, but these are the games you want to play as a kid against those teams.”

Blind’s sentiments were echoed by boss Michel, who said: “We’re going to enjoy our game. Our league is not Madrid, Barca and Atletico. We just want to keep this successful run going as long as possible.”