Barcelona new boy Lewandowski battles old Bayern Munich partner Muller

Thomas Muller turns 33 on Tuesday. He will greet the milestone with his usual wide grin and plenty of chatter before focusing on the highest-profile fixture yet of his 15th season as a senior Bayern Munich player, a Champions League collision with Barcelona.

And turning up for the birthday will be the greatest ally of Muller’s storied career.

The difference is that, unlike in any of past eight Septembers, Robert Lewandowski will be coming to Muller’s home turf of Munich’s Allianz Arena as a guest, wearing the jersey not of Bayern in whose colours he partnered Muller 332 times, but of Barca who the prolific Pole joined in the summer.

The welcome given to him by Muller, the talkative MC of Bayern’s dressing-room, will be warm. Though the reactions of some in the 70,000-plus crowd may be more mixed.

Lewandowski, 34, stands one place off the top of the German champions’ all-time goalscorers’ list. But he left at least a year earlier than supporters, teammates, the head coach Julian Nagelsmann and most of the club’s executives wanted him to.

How much is Lewandowski missed? A glance at the Bundesliga table suggests the club’s coup in bringing in a high-class replacement, Sadio Mane from Liverpool, has not achieved the smoothest of transitions yet. Bayern sit third in the table and have drawn their last three domestic fixtures.

It marks a poorer start to a campaign than any Lewandowski experienced in his eight years at Bayern. Muller has to go back all the way to 2010 to recall such a low yield of points – 12 – from an opening six matches.

Muller was angry, he told reporters, after Bayern had twice let a lead slip against Stuttgart on Saturday, but the humour for which he is known returned in the lead up to his reunion with "Lewy", as Lewandowski is nicknamed.

“Sadio has been joking with me that, under no circumstances, should I pass to Lewy,” smiled Muller.

The Muller pass to Lewandowski was, for the best part of a decade, a routine, the key to one of the most productive tandems in sport. In all, Muller directly assisted 64 of Lewandowski’s 344 Bayern goals, more than any colleague. Muller can thank Lewandowski for 16 assists towards his career tally of 228 club goals.

“It was a relationship that developed over years,” Muller replied when asked how his developing understanding with Mane, who typically takes up wider and deeper positions than Lewandowski, differed.

“With Lewy, it wasn’t something that was there from the start. What we don’t have now is a traditional target centre-forward and in some games this season that’s been a benefit – it’s harder for opponents to track runs.”

Yet Muller is old and wise enough to know that if Lewandowski proves the match-winner for Barcelona, against whom he scored twice in the group phase last season, Bayern will be deemed a weakened side for his absence.

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“That will be something we’re attacked for. You can always find arguments for and against. The debate about Lewy will go on until such an outstanding goalscorer is no longer around.”

Nagelsmann, critical of Barcelona’s aggressive spending during the summer – the €45 million on Lewandowski was part of an outlay of over €150m – acknowledged the threat of the ex-Bayern record-breaker would be a principal concern.

“He's the most dangerous player,” said the Bayern coach. “He has a great presence in the penalty box. But he needs players delivering to him. We have to stop the passes and crosses reaching him. There are other good players at Barcelona, too.”

Among them the many who have been lining up to praise Lewandowski for how quickly he has found his goalscoring groove in Spain and established fruitful links with teammates.

“I have been surprised by how much he talks on the pitch,” said Eric Garcia, the Barca defender, “and how he’ll tell you what’s going to happen before it happens.”

Those remarks speak of the complicity between Lewandowski, who has nine goals from six Barca outings, with his new attacking partners.

He’s been assisted and been the assister to Barca’s teenage starlet Ansu Fati; he’s been the beneficiary and a chaperone for winger Ousmane Dembele’s dazzling start to this, the sixth season of his up-and-down Barcelona career.

Bayern represent a tougher hurdle than Cadiz, Real Sociedad, Sevilla, Valladolid and Viktoria Plzen, against whom Lewandowski has racked up his goals so far.

“It's a nice way to determine where we stand, up against a side who have upgraded,” said Nagelsmann, who oversaw victory over Internazionale, the group’s other heavyweights, on match day one. “They have newcomers playing big roles, like Lewy. I think he’ll still score a lot of goals there. He's used to 40 per season and he's on the right track for that in Spain.”

Barcelona new boy Lewandowski battles old Bayern Munich partner Muller

Champions League Group C clash sees former attacking allies on opposing sides

Barcelona 5 Viktoria Plzen 1 - player ratings