Why Chelsea's Koulibaly move spells bad news for Arsenal
Koulibaly, 31, joins the West London club for €40 million, and is expected to be joined by one more defensive signing as well as Raheem Sterling, who made a move from Manchester City last week.
The Senegal international will be tasked with replacing the outgoing Andreas Christensen and Antonio Rudiger, with Chelsea currently left without many senior centre-back options.
However, Chelsea's addition of Koulibaly could inadvertently harm Arsenal's chances this season.
De Ligt, who is also wanted by Chelsea, is set to join Bayern Munich after the Dutchman expressed his desire to leave Juve for the Bavarian outfit. Bayern's sporting director Hasan Salihamidzic has expressed that he remains "optimistic" that a deal for De Ligt will be completed before the end of the window.
But, with De Ligt on his way out of Turin, Juventus need to sign a replacement. That need is accentuated by the fact that Giorgio Chiellini has left the club to join LAFC after his contract expired, and Merih Demiral has been permanently sold to Atalanta.
Juventus' De Ligt replacement
It's been reported that Juventus' first-choice to replace De Ligt is, in fact, Koulibaly. However, with Chelsea now completing a move for him, they've been forced to turn to their second-choice.
Unfortunately for Arsenal, that man is their Brazilian centre-back Gabriel Magalhaes. Juventus are aware that it'll take a bid of at least €40m for Arsenal to sell the defender, but they are keen on adding him to their ranks.
It's understood that while Gabriel is 90% committed to Arsenal, he will listen to Juventus' offer, which could spell trouble for the Gunners, especially given William Saliba's return from Marseille means Gabriel's place in the starting XI isn't guaranteed.