Messi severed his 20-year connection with the Catalan giants at the start of the month after leaving the club following the expiration of his contract.
The Argentinian is yet to make his debut for new club Paris Saint-Germain with La Blaugrana enduring a mixed start to the season.
An opening day win over Real Sociedad was followed by a battling draw at Athletic Bilbao this weekend and Koeman stated the team missed Messi against the club he has scored the most goals against in his club career.
“I don’t like to always talk about it, but we are talking about the best player in the world”, as per reports from Marca.
“The opposition is more afraid when Messi is there.
“If you give Leo a pass, he usually doesn’t lose the ball. You can tell he is not here. We know that but it can’t be changed.”
La Blaugrana have a full seven days rest before their next outing with Getafe going to the Camp Nou on August 29 before both players head off on international duty next month.
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