Italian giants Napoli are waiting for Manchester United to bid for central defender Kalidou Koulibaly, according to La Gazzetta Dello Sport. The 29-year-old has been linked with a move to both Manchester clubs, with City reportedly making a €70 million plus add-ons bid for the Senagalese. Ole Gunnar Solskjaer is in the market for a central defender to partner captain Harry Maguire. Koulibaly fits the bill for United, as a fast, strong central defender who is adept on the ball. Pep Guardiola, also an admirer of the Senegal defender, is looking to overhaul his defensive ranks, with Nathan Ake already making the switch from relegated Bournemouth. Interestingly, both Manchester sides were eliminated from European competitions this season due to defensive errors at the back. Manchester City have reignited their interest in Napoli centre-back Kalidou Koulibaly following their exit from the Uefa Champions League.Reports claim City are preparing to offer as much as £63 million for the 29-year-old but it does not meet Napoli's valuation of £81m. 👀 pic.twitter.com/QGrf5XHWYj— Goal Africa (@GoalAfrica) August 18, 2020Manchester United to make a bid for KoulibalyOle Gunnar Solskjaer will look to add to his central defensive contingent ahead of the next Premier League season. The Manchester United manager has preferred using Victor Lindelof and Harry Maguire as a central defensive partnership for the majority of this season. Sergej Milinkovic Savic of SS Lazio compete for the ball with Kalidou KoulibalyHowever, due to the high line United prefer to play, the Red Devils have been exposed by pace at the back regularly. Gabriel of Lille, Pau Torres of Villarreal and Ben White of Brighton have been linked with a move to Manchester. The United manager will also look to offload Marcos Rojo, Chris Smalling and Phil Jones this summer. Smalling, who had an excellent season at AS Roma, has attracted interest from the likes of West Ham United and Juventus.It will be much more difficult shifting the other two as they have hardly managed to play games this season due to injuries. 🗣 "He won't leave at the price they think they will get, nobody will arrive at 90M, the most interested club is Man City" @DiMarzio with the latest on Kalidou Koulibaly's transfer news pic.twitter.com/pDFI0LtkLP— Football Daily (@footballdaily) August 17, 2020Apart from central defence, left-back has also been a problem position for Manchester United. Luke Shaw has had a stop-start season, missing the last stage of the Europa League due to an ankle injury. Brandon Williams has played admirably for the first team but has his limitations due to being a predominantly right-footed player on the left. Sergio Reguilón, who gave Manchester United a torrid time in Germany, could be a potential option to fill the position.