Lewandowski completed a £42 million move from Bayern Munich overnight and is the Blaugrana's fourth signing of the summer.
It is expected he will take the number nine shirt, currently worn by Memphis Depay, even if the Netherlands international fails to secure a transfer away.
If you want to buy one however, you are out of luck. Lewandowski shirts are unavailable at the megastore outside the Camp Nou thanks to a letter shortage.
A fan attempted to purchase a shirt with the forward's name on the back and was told a firm no by a man on the checkout.
"Why can't we buy jerseys with Lewandowski?", he asks before being told, "Because we don't have the letter W and because he has two in his name, we have run out."
Martin Braithwaite is the only other Barcelona player with the letter 'W' in his name and given his low standing in the squad, it is likely Lewandowski has caused the shortage.
The 33-year-old has joined up with his new teammates in Miami as part of Barcelona's pre-season tour after pleading to leave Bayern in recent weeks.
He was forced to report for Bayern training last week and looked like he wanted to be anywhere else in the world.
Lewandowski had one year remaining on his deal with the Bundesliga giants and said his story with the club was 'over' back in May.
The Poland international is looking forward to a new challenge in La Liga and cannot wait to get started.
He told Barcelona's official website: "I'm finally here. I'm delighted to be at Barca. The last few days have been very long, but the deal is done and now I can focus on a new chapter and challenge in my life.
"I've always wanted to play in La Liga and for the big clubs. I'm here to help Barca get back to the top and win as many titles as possible."
In addition to Lewandowski, manager Xavi has added Andreas Christensen, Franck Kessie and Raphinha to his squad.
The club continue to work on deals for Sevilla defender Jules Kounde and Manchester City midfielder Bernardo Silva too.
Featured Image Credit: @forcabarca_ar/Twitter & Barcelona
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