Key talking points ahead of the second round of Champions League games in the group stage:
United struggles
With 55 shots in the last two games, no goals and a pair of 1-0 losses, Manchester United's attack is looking blunt. That's even with Cristiano Ronaldo back at the club, although he only played in Saturday's defeat to Aston Villa and not the League Cup exit to West Ham.
There will be little room for error in the Champions League if Villarreal can't be beaten at Old Trafford in Group F on Wednesday after United opened two weeks ago with a loss to Young Boys.
Villarreal beat United in last season's Europa League final and Ole Gunnar Solskjær will want to avoid United dropping into Europe's second-tier competition again after benefiting from so much investment in the squad.
Madrid's attacking power
Real Madrid hosts Sheriff on Tuesday needing Karim Benzema and Vinícius Júnior to quickly get back in form after faltering in a 0-0 draw against Villarreal in the Spanish league this weekend.
After outscoring opponents 22-8 in its first seven matches in all competitions, Real couldn't find the net for the first time this season. Sheriff comes to Madrid leading Group D after opening its first Champions League campaign with a win against Shakhtar Donetsk.
Rodrygo was the scorer for Madrid in the team’s 1-0 win at Inter Milan in its Champions League opener.
Who's in goal for PSG?
Mauricio Pochettino remains evasive about who is Paris Saint-Germain’s first-choice goalkeeper and whether Keylor Navas or new signing Gianluigi Donnarumma will start against Manchester City in their Group A match in Paris on Tuesday.
Not a bad dilemma for a coach to have. Navas was one of the best goalkeepers in the world last season while Donnarumma ended it by helping Italy win the European Championship. Navas has started PSG's last two games and looked in good form, but Donnarumma might not be satisfied with the backup role.
Up front, Pochettino hopes to have Lionel Messi back in attack as the Argentine shakes off a minor knee injury that sidelined him for two games. Messi’s last goal in the Champions League came for Barcelona against PSG at Parc des Princes in last season’s last-16. He had a penalty saved in that game — by Navas.
Dortmund's wait
Borussia Dortmund is sweating on the fitness of star striker Erling Haaland and influential captain Marco Reus for Sporting Lisbon’s visit on Tuesday in Group C.
Dortmund slumped to a 1-0 loss at Borussia Mönchengladbach in the players’ absence on Saturday, when it was apparent how reliant the team had become on the goals that the pair provide.
Haaland scored 11 goals and set up four more in seven games so far this season, while Reus contributed one goal and five assists in his seven games across all competitions. Both were injured in training on Friday.
Red-hot Benfica
Benfica hosts struggling Barcelona on Wednesday while enjoying a great start to its season with eight wins in 10 matches. And the only setbacks were draws against PSV Eindhoven in the qualifying round of the Champions League and at Dynamo Kyiv in the Group E opener.
There was some controversy in the team’s win at Vitória Guimarães this weekend, with coach Jorge Jesus exchanging a few words with forward Darwin Núñez during the game and technical director Luisão arguing heatedly with central defender Lucas Veríssimo after the final whistle.
It was calmer for once for Barcelona as a 3-0 Spanish league win over Levante took some heat off coach Ronald Koeman. The team had been on a three-match winless streak that started with a demoralizing 3-0 loss to Bayern Munich in the Champions League.
Problems for Juventus
Juventus’ problems deepened as key forward Paulo Dybala sustained an injury and will miss Wednesday's home game against Chelsea. Dybala scored the opening goal of Juve’s 3-2 victory over Sampdoria on Sunday but left the field 10 minutes later in tears after pulling up suddenly, clutching the back of his leg.
It was another unconvincing win for Juventus and only its second in the league this season. The Bianconeri defense will face a sterner test from Romelu Lukaku and the Chelsea attack in the Group H match.
Atletico stutters
Atlético Madrid visits AC Milan on Tuesday in Group B and is still waiting for a breakthrough performance from Antoine Griezmann in his return to the club. Griezmann is winless in eight matches with Atlético this season.
The defending Spanish champion has struggled recently with only one victory in its last four matches, including a 0-0 home draw against Porto in its first Champions League match. Its last game was a stunning 1-0 defeat at then last-placed Alavés in the Spanish league.
Sevilla injury
Sevilla may be without one of its top forwards when it visits Wolfsburg. Youssef En-Nesyri hurt a muscle and had to be substituted early in the second half of the team's 2-0 win against Espanyol in the Spanish league on Saturday.
En-Nesyri had scored his third goal of the season in the first half. Sevilla is coming off two straight wins and is third in the Spanish league. The Group G match is on Wednesday.
Porto unbeaten
Porto hosts Liverpool coming off an unbeaten start to its season with five wins and three draws, including at Atlético Madrid to begin its Champions League campaign. Porto won its three matches at home by outscoring opponents 10-0.
Veteran central defender Pepe is still listed as doubtful for Tuesday's Group B match because of a left leg muscle injury sustained in the 0-0 draw against Atlético in Madrid.
Weah goal
As the son of a president who was once among the world's best strikers, Timothy Weah has a hard act to follow. He's still searching for a first goal of the season when Lille travels to face Salzburg in Group G on Wednesday.
The 21-year-old American forward is the son of George Weah, who is Liberia's president since 2018 and won the Ballon d'Or in 1995. His son is slowly making a name for himself with northern French club Lille but there were only five goals last season.
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