PSG's Lionel Messi reacts during the Champions League Group A soccer match between Club Brugge and PSG at the Jan Breydel stadium in Bruges, Belgium, Wednesday, Sept. 15, 2021. AP
Paris Saint-Germain were poor on Lionel Messi's first start, while Barcelona's troubles were there for all to see in their loss to Bayern Munich, Liverpool were exposed by AC Milan and Jack Grealish had a great night for Manchester City.
AFP Sport looks at the talking points from the first round of action in this season's Champions League:
PSG's 'ghost-like' galacticos
The arrival of Lionel Messi and their decision to reject Real Madrid's advances for Kylian Mbappe have made Paris Saint-Germain the favourites to win the Champions League.
On Wednesday coach Mauricio Pochettino lined up Messi, Mbappe and Neymar together for the first time, with the Argentine making his first PSG start against Club Brugge.
It did not turn out as they hoped, as Paris were held to a 1-1 draw despite Ander Herrera giving them the lead.
Indeed they were fortunate to leave with a point, while Mbappe went off injured. Sports daily L'Equipe's front-page headline declared PSG as "ghost-like" rather than galactic.
Pochettino later pleaded for time for his superstar attack to get to know each other better, but he also admitted Mbappe had twisted an ankle. They play Manchester City next.
Grealish makes mark
City's £100 million ($139m) splash on a player with no Champions League experience was looked upon with scepticism across Europe as a classic sign of Premier League excess.
However, Grealish showed he is ready for the biggest stage with a scintillating display that put RB Leipzig to the sword as City triumphed in a 6-3 goalfest.
Grealish made the opener for Nathan Ake and capped his performance with a goal in characteristic fashion by cutting onto his right foot and firing into the far corner.
"When I'm in that position, running into the area, I'd back myself one on one against anyone," said Grealish.
City have now scored 16 goals in their last three home games.
Meanwhile the defeat for Leipzig piles pressure on their American coach Jesse Marsch, who oversaw a 4-1 loss to Bayern Munich at the weekend.
Leipzig have lost four of their six competitive games under Marsch.
Barca face up to reality
That Barcelona are a declining force has been obvious for some time, since well before Lionel Messi departed. Tuesday's comprehensive 3-0 home defeat against Bayern merely served to underline how far they have fallen.
A year after their 8-2 win over Barca in Lisbon, Bayern might have scored more at the Camp Nou but in the end settled for three thanks to Thomas Mueller's opener and Robert Lewandowski's double.
The defeat was met with a sense of resignation by Barcelona supporters and by Gerard Pique, who admitted: "It is what it is. We are what we are, that's the reality."
Barcelona failed to muster a single shot on target and coach Ronald Koeman's position is under increasingly intense scrutiny before the Catalans go to Benfica in their next European game.
Milan expose Liverpool weaknesses
Liverpool got the better of another Champions League classic against AC Milan, coming from behind to win 3-2 at Anfield.
Liverpool blitzed the visitors in a fast start, yet somehow found themselves 2-1 down at half-time due to five minutes of meltdown before the break where Jurgen Klopp admitted they "lost the plot".
Their relative lack of strength in depth was exposed -- the Reds lack a clinical centre-forward and Divock Origi did little to justify his case for more minutes in a rare start.
At the other end, Virgil van Dijk's return has seen Liverpool concede just once in four Premier League games.
Klopp rested the Dutchman as he works his way back from a long-term knee injury and his presence was badly missed.
Inter enthusiasm takes hit
The optimism surrounding Inter Milan after a solid start to the season has wobbled after being sucker-punched by Real Madrid.
Fan have been angry at the Italian champions' Chinese owners over the sale of star striker Romelu Lukaku to Chelsea. His replacement Edin Dzeko has started the season well but he fluffed a series of great chances in the 1-0 defeat at San Siro.
Both Dzeko and strike partner Lautaro Martinez insisted Inter deserved more than to lose to a last-minute Rodrygo strike but their wastefulness is starting to look like a problem, with the same profligacy in front of goal evident in their 2-2 draw at Sampdoria on Sunday.
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