The Champions League delivered another entertaining slate of group-stage action this week. Below, we dissect the biggest talking points from Matchday 6 in Europe’s premier club competition.

What was Walker thinking?

It’s probably safe to assume that losing to RB Leipzig didn’t annoy manager Pep Guardiola nearly as much as his first-choice right-back Kyle Walker picking up a straight red card in Manchester City’s last Champions League group stage match.

With Leipzig on their way to a 2-1 victory over a City side that clinched first place in Group A last matchday, Tuesday’s encounter in Germany suddenly had very relevant consequences for Guardiola’s team after Walker imploded with a senseless challenge on Andre Silva.

The foul was clearly one born out of frustration, as Walker battled with the Leipzig attacker along the touchline before kicking at the back of his legs. The dismissal means that Manchester City will be without the England international in the first leg in the round of 16 through suspension.

Walker’s absence in the next round is a massive blow for Guardiola regardless of which team the Premier League club gets paired with at the round of 16 draw next week. Fortunately, Guardiola has another world-class full-back in Joao Cancelo, who will presumably move across the pitch while Oleksandr Zinchenko deputizes at left-back.

Haller takes long, winding road to history

Consider Sebastien Haller’s unlikely journey into the record books. Here was a striker who joined West Ham United in 2019 for a club-record £45 million, struggled to score in the Premier League, and became the butt of jokes for his many near-misses. In January, West Ham cut their losses, selling Haller to Ajax at nearly half the cost.

Then, just as things looked up, with a goal and an assist on his full debut, an administrative error cost him a place in Ajax’s Europa League squad.

Fast-forward to Tuesday, and the air around Haller is much lighter. After scoring in Tuesday’s 4-2 win over Sporting Lisbon, the 27-year-old became just the fourth player behind Cristiano Ronaldo, Lionel Messi, and Robert Lewandowski to reach 10 goals in the Champions League group stage. Four of them came on his tournament debut in September, a 5-1 rout of Sporting that showcased what Haller is really all about. He eluded defenders with late runs into the box, wedged himself between them, and pounced when opportunities struck.

He proved that all notions about his time in England were misleading.

Milan will benefit from tough exit

The reality is that AC Milan are still a work in progress, and advancing from this year’s Group of Death was always going to be difficult. The majority of Milan’s starters hadn’t played much, if any, Champions League football before this season. Factor in questionable officiating – namely referee Cuneyt Cakir’s ridiculous decision to send off Franck Kessie on Matchday 2 – and it’s a wonder the Rossoneri even had a chance to progress entering the final match of the group stage.

Milan did plenty of things right – and they did a host of things wrong. They pressed well, showed personality and style away from home, led Liverpool at Anfield, and beat Atletico Madrid at the Wanda Metropolitano. They just couldn’t win at home. A number of errors cost them in Tuesday’s 2-1 defeat to Liverpool, which eliminated Milan from the Champions League and European competition altogether. A defensive lapse allowed Mohamed Salah to equalize, and a giveaway led to Divock Origi’s winning header.

But finishing fourth isn’t so much a failure. It’s a combination of bad luck and circumstance. Milan didn’t have a fully fit squad for any of the six group stage fixtures. They did what they could in a difficult group. Now, they can focus exclusively on Serie A, which they’re currently leading, and apply the lessons they learned from the Champions League. This is just the start of an “interesting” project, as Liverpool manager Jurgen Klopp described it.

Liverpool’s youngsters hold their own

Klopp could only smile when he was asked about the performance of 19-year-old academy graduate Tyler Morton.

“I don’t want to make his life more complicated than it is already with playing at such a young age for a club like Liverpool, in a game like this, with a performance like this, so I think we should all calm down,” the manager told reporters. “But it was really good tonight.”

Morton showed incredible composure to protect Liverpool’s backline, completing a game-high three interceptions without conceding a single foul. He largely neutralized opposing numbers Kessie and Sandro Tonali, and he helped his team defend by committee.

Center-back Nat Phillips also put his skill on display. The 24-year-old was calm in possession and outstanding in tight spaces. He outdueled Zlatan Ibrahimovic, boxing him out of dangerous areas with the help of defensive partner Ibrahima Konate.

Klopp’s decision to rotate his squad in an otherwise insignificant fixture could pay dividends down the road. The German should now have considerably more confidence in the depth of talent he has on the bench.

Atletico win another game in the trenches

Atletico Madrid went back to their scrappy roots Tuesday in Portugal, showing blood, guts, and tears to seal a place in the round of 16. Diego Simeone’s side started the day in dead last in Group B, but its trademark tactics earned the club the victory it needed to advance.

The red cards, the sideline brawls, the late fouls and challenges – it was quintessentially Atletico. Simeone’s team played with the same sinister spirit that fueled its rise in the early 2010s, hitting Porto on the counter and, more importantly, drawing them into a good old-fashioned street fight. Atletico took the early lead and built on it despite going down to 10 men. Porto couldn’t keep their cool long enough to get an equalizer.

Simeone’s winning formula has always included a healthy dose of suffering, and Atletico have faced plenty of adversity this season. The reigning La Liga champions fell 10 points behind Real Madrid with Sunday’s 2-1 loss to Mallorca – their third defeat at home since late August – renewing criticism of Simeone’s commitment to a hard-working, defensive foundation with a group of clearly talented, attack-minded players.

But they dug in Tuesday, running 6.5 kilometers more than their opponents to secure the 3-1 victory.

“This match and this group stage campaign sums up just what Atleti is all about,” Antoine Griezmann, UEFA’s man of the match, said afterward. “We are a true group, and we need everyone to do their bit to get to where we want to. We never stop believing.”

Chelsea make life difficult for themselves

The consequences of Chelsea’s disappointing end to the Champions League group stage will be a major talking point heading into Monday’s draw.

After the Blues mounted a second-half comeback to take a 3-2 lead and set themselves up for a first-place finish, Zenit St. Petersburg snatched an equalizer in stoppage time to condemn Chelsea to second in Group H behind Juventus. It was a stunning turn of events made even more surprising given how dominant Chelsea’s defending has been since the beginning of last season’s Champions League campaign.

Having already secured a berth into the next round, Chelsea started the contest off brightly before Zenit stormed back late in the first half to take a 2-1 lead. The Blues overturned the deficit but couldn’t hold on as Magomed Ozdoev’s wonderful strike capped off a thrilling night in Russia.

While the result will undoubtedly come as good news for Juventus and Zenit, the same can’t be said for the four group winners – Ajax, Real Madrid, Bayern Munich, and Lille – that now face the possibility of having to play the Champions League holders in the next round.

Questions remain for Juve

Juventus – somewhat fortuitously – secured top spot in Group H on Wednesday thanks to their 1-0 win over Malmo and Chelsea’s aforementioned collapse against Zenit. On the surface, it’s cause for celebration; the last-16 draw will, in theory, be far more forgiving than it would have been had the Bianconeri finished second.

But Wednesday’s contest once again highlighted Juventus’ issues in front of goal. Chance creation is a serious issue that Massimiliano Allegri has yet to rectify, and neither Alvaro Morata nor Moise Kean has managed to emerge as the first-choice No. 9.

Kean – who returned to the club this past summer and often looks more lively than his Spanish counterpart – scored the lone goal Wednesday with an instinctive header. But the 21-year-old also spurned two glorious opportunities later in the match. Morata, 29, continues to be indecisive inside the penalty area and is too easily flustered when things don’t go his way.

Kean is almost certainly the long-term answer, at least among the available options, but he’s not a finished product.

Juventus have scored just 32 goals in 22 matches this season. Unless they find a way to carry a more consistent attacking threat, it won’t matter who they draw for the round of 16.

Another reality check for Barcelona

Xavi didn’t think Barcelona needed a miracle to beat Bayern Munich. In reality, they needed much more than that.

Barcelona turned in yet another meek Champions League performance Wednesday, losing 3-0 to Bayern for the second time in four months. They fired two shots on target while settling for 45% possession, showing no urgency, organization, or cohesion. Bayern dominated Barcelona in every aspect, just as they did on Matchday 1 and in years prior. Wednesday’s result further underscored the gulf between Barcelona and the game’s elite.

Ultimately, the Blaugrana need to adjust their expectations. Xavi tried to get Barcelona to press high, but it simply didn’t work against Bayern’s more formidable and tactically astute players. There’s promise in Barcelona’s ranks – Gavi, Memphis Depay, Pedri, Ronald Araujo, Frenkie de Jong, and Ousmane Dembele all possess great technique – but they’re not there yet. Not as a unit, anyway. It will take more than just a few games for this side to execute Xavi’s vision.

Barcelona can’t expect a quick fix. Those don’t happen at this level. The club must keep faith in Xavi, commit to a strategy and philosophy, and bet on the right players. Forget the fact that Barcelona are playing in the Europa League for the first time in nearly two decades. This is who they are, and playing in Europe’s second tier may be a better learning experience than a last-16 thrashing at the hands of another continental heavyweight.

Historic Group G finale lacks drama

Heading into Wednesday’s group-stage finale, Group G promised to provide some of the late twists and turns that have become staples of the Champions League. All four teams – Lille, Red Bull Salzburg, Sevilla, and Wolfsburg – entered the day facing numerous possibilities; qualification for the last 16, a place in the Europa League, and complete elimination from Europe were all on the table for each of them. It was, quite literally, all to play for.

Sadly, the drama never really materialized.

Lille and Salzburg, who started the day occupying the quartet’s top two spots, beat Wolfsburg and Sevilla, respectively, ensuring things finished the way they started.

You can’t win ’em all.

Not that either side will care, of course. Lille, languishing in Ligue 1 this season after a tumultuous summer, are into the knockout stages of Europe’s premier tournament for just the second time. Salzburg, meanwhile, are the first Austrian team to ever progress this far.

Both clubs will almost certainly be viewed as underdogs in the last 16. But with rising stars like Jonathan David and Karim Adeyemi in the mix, don’t rule out an upset.

Delicious last-16 matches on tap

With the group stage coming to a close Wednesday – notwithstanding Atalanta’s postponed tilt with Villarreal – fans learned the potential matchups for the round of 16. The possibilities are tantalizing.

Chelsea’s surprising draw against Zenit St. Petersburg – and subsequent drop to second place in Group H – creates mouthwatering possibilities that wouldn’t exist had the reigning champions taken care of business in Russia.

Thomas Tuchel’s men could meet Real Madrid, high-flying Ajax, or – most enticingly for neutral fans – mighty Bayern Munich. The entire field of group winners, meanwhile, is open to Paris Saint-Germain – bar Manchester City and Ligue 1 peers Lille.

None of the seeded sides will want to tangle with Lionel Messi, Kylian Mbappe, and – assuming he’s fit – Neymar come February.

Atletico Madrid may be wounded this season – they barely squeaked through to the last 16 – but beating Diego Simeone’s side in a knockout situation is always a difficult proposition. A rejuvenated Inter Milan squad is also lurking for one of the group winners.