Laurent Koscielny has hailed Manchester United target Kalidou Koulibaly "one of the best central defenders in Europe".
The Arsenal star came up against Koulibaly in the Gunners' 2-0 win over Napoli in the Europa League on Thursday.
The Senegal international actually scored an own goal in Napoli's defeat, but still caught Koscielny's eye for all the right reasons.
"I really like Kalidou Koulibaly at the back," said the Frenchman.
"He's one of the best central defenders in Europe. He is so strong physically but reads the game really well and is very comfortable on the ball.
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"I like his attitude too. He is calm, respectful and with good values.
"It will be great to play against him and whoever plays up front for us tonight will have a big fight on his hands."
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Manchester United were strongly linked to the centre-back when Jose Mourinho was in charge in the summer, but a transfer never transpired.
The Red Devils could still make a move for him when the transfer window re-opens in a few months time, but other clubs are also keen on signing Koulibaly.
