The Blues currently have four recognised first-team centre-back options, with Senegal international Kalidou Koulibaly having been signed from Napoli in order to support Thiago Silva, Malang Sarr and Trevoh Chalobah.
But with Tuchel having employed his traditional 3-4-1-2 system since arriving at Chelsea at the beginning of 2021, using it to make the Blues European and world champions, the German believes he requires another defender who can play on the left of the central three.
‘Toni [Rudiger] played on the left side and was not a left-footed guy, so maybe Kalidou can play there because he plays in a back-four on the left side, but let’s see what is possible.
‘It is not only about bringing players in for numbers; we need numbers, we also need quality so we will make some decisions late, not only about players but also about systems. Ideally we would have a left-footer.’
Chelsea have been in the market for new centre-backs this summer as they look to reinforce their defence following the departures of Antonio Rudiger and Andreas Christensen on free transfers, the former joining Real Madrid and the latter Barcelona.
They were heavily linked with a move for Matthijs de Ligt after he made his desire to leave Juventus clear, but the Dutchman eventually opted to join Bayern Munich instead.
Chelsea have also signed Manchester City forward Raheem Sterling for £45m so far this summer.
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