Champions League Thursday takeaways: Monaco dominates Barcelona, Wirtz and Raya impress

The first week of the new-look Champions League came to an end on Thursday, with Barcelona and Arsenal both in action.

But neither of Thursday's star clubs were able to start with a win, one falling to a disappointing loss and the other requiring goalkeeping heroics to take home a point.

Here are the main takeaways from Thursday's matches.

Monaco dominates 10-man Barcelona Having won all five of its games in La Liga, Barcelona's Hansi Flick era hit its first bump in the road as the Blaugrana were well-beaten by AS Monaco.

An early red card for Eric García for a professional last man foul on Takumi Minamino gave the 2004 Champions League finalist a huge boost, and the French side took full advantage.

"Today, you see this situation with a red card after 11 minutes, it changed our match plan. We have to accept it, this happens," Flick told reporters after the game.

Things went from bad to worse for Barça in the 16th minute when Maghnes Akliouche gave the home team the lead with an excellent strike, coming in off the right wing and lashing the ball past Marc-André ter Stegen at his near post.

Barcelona did strike back just before the half-hour mark when Lamine Yamal scored a near carbon-copy of Akliouche's goal at the other end. It was the 17-year-old's debut Champions League goal after his eye-catching brace against Girona at the weekend.

But it was Monaco's own rising star, George Ilenikhena, who would make the headlines. With the home team putting on constant pressure, the Nigerian striker scored the winner in the 71st minute, beating ter Stegen at his near post again.

In doing so, the 18-year-old became Monaco's youngest ever Champions League goalscorer, breaking the previous record set by Kylian Mbappé in the 2016/17 season, the last time the club progressed to the knockout stages of the competition.

"We had chances, but they deserved to win," said Flick. "I have told the team to lift their heads up because they are disappointed, but we have to focus on Sunday (at Villarreal), which is our next game. It's the time to recover. Hopefully, players will be back with a lot of energy."

David Raya miracle saves Arsenal After Liverpool's 3-1 win over AC Milan and Manchester City's 0-0 draw with Inter, the Champions League saw its third Anglo-Italian clash of the week as Atalanta hosted Arsenal.

With Atalanta having lost three of its first five games, and Arsenal arriving on the back of a win against local rival Tottenham Hotspur, many expected the Gunners to record a comfortable victory.

Instead, the favorite needed heroics from goalkeeper David Raya to keep the game scoreless.

After Atalanta was awarded a penalty for Thomas Partey's foul on Éderson early in the second half, Raya kept out Mateo Retegui's effort with an excellent save to his right, before pulling off a remarkable second save to his left to scramble away Retegui's header from the rebound.

The eventual 0-0 draw may not have been the result Arsenal was looking for, but it could have been much worse were it not for its goalkeeper.

"We needed two of the best saves that I've seen in my career from David to stay in the game," said manager Mikel Arteta. "The work with the goalkeeping coach, Iñaki, he knew (which way to go) and they did the job and the execution of that first one was unbelievable. But the second one, I thought the ball was in.

"He's showing the kind of person he is and his role as a leader in the team. That's very important."

Florian Wirtz shines on Champions League debut It took Florian Wirtz just five minutes of Champions League football to grab his first goal in the competition.

The Bayer Leverkusen star looked a class above host Feyenoord, firing a left-footed shot from the edge of the box into the bottom corner to get Xabi Alonso's men off to the perfect start.

After Álex Grimaldo doubled Leverkusen's lead, Wirtz popped up again in the 36th minute, volleying a Jeremie Frimpong cross past goalkeeper Timon Wellenreuther.

Wellenreuther's own goal just before half-time completed the rout.

"We got off to a very good start today, and I'm, of course, happy that I was able to score two goals," Wirtz told UEFA.com . "It was a really great evening. I think, above all, the victory stands out and such a clear win at that."

Wirtz joined Harry Kane, Michael Olise and Jamie Gittens as the only players to score more than one goal in the Champions League this week; all four play for German clubs.

Difficult first week for Swiss Model revamp The newly revamped Champions League format, which follows a Swiss Model in which all 36 participants are organized into one league table, was designed to create more games between Europe's top teams earlier in the competition.

However, many fans on social media have been left unconvinced by the changes after a number of disappointing games during the opening week.

The rematch of the 2023 Champions League final between Manchester City and Inter Milan was the standout fixture of the round but ended in a 0-0 draw amid warnings from City midfielder Rodri that the new system – which adds two extra games to each team's schedule – could lead to players going on strike to protest being overworked.

With that 0-0 being the only game between two teams from pot one this week, fans also called out the perceived persistence of mismatches between very strong and relatively weak teams.

The clearest example of a gulf in quality came in Bayern Munich's 9-2 win over Dinamo Zagreb, in which Bayern's own fans held up banners reading "Too many games," "Too much injustice" and "Too much financial imbalance," along with a larger banner which read "Back to the roots, undo new CL format."

Fans on social media tended to agree with one posting on X , formerly known as Twitter: "This new Champions League format is so weird and hard to get." Another wrote : "Could lose five games, then beat Slovan Bratislava, Sturm Graz and Dinamo Zagreb and nine points gets you through. Barely competitive until the RO16."

With seven game weeks remaining before the knockout stages, it remains to be seen how the new format will play out. However, as time goes by, fans might grow accustomed to everything.

Even if not, all eyes will surely be on the next matchday when the Champions League returns on October 1, highlighted by Arsenal vs Paris Saint-Germain.

Thursday's resultsHome vs. away (winners in bold)

Crvena Zvezda (Red Star) 1-2

Feyenoord 0-4 Bayer Leverkusen

Stade Brestois

Atalanta 0-0 Arsenal

Atlético Madrid