Manchester United manager Erik ten Hag has reportedly set a deadline for Red Devils chiefs to seal a deal for Barcelona midfielder Frenkie de Jong.United's pursuit of the Dutch midfielder is becoming the longest-running saga of the summer transfer window. There have been many twists and turns with regard to De Jong, 25, potentially arriving at Old Trafford.As of yet, Manchester United have failed to agree to a fee with Barcelona, having most recently had a bid of €60 million + add-ons rejected (per Marca).Journalist Jacque Talbot reports that Ten Hag wants the signing sealed before the pre-season starts.UtdPlug@UtdPlug NEW: Frenkie de Jong begins to be very close to Manchester United. Sources of the negotiation confirm that the talks have advanced very positively in recent hours. @Sport #MUFC 52865🚨🇳🇱 NEW: Frenkie de Jong begins to be very close to Manchester United. Sources of the negotiation confirm that the talks have advanced very positively in recent hours. @Sport #MUFC 🔴The Red Devils fly to Thailand in early July for their first pre-season clash against fierce rivals Liverpool on July 12.Ten Hag will be hoping to have De Jong in his squad once that game comes around. He has reportedly become frustrated with the lack of progress (per The Athletic).The Red Devils are in stark need of midfield reinforcements with Jesse Lingard, Paul Pogba, Nemanja Matic and Juan Mata all heading out of Old Trafford.The Dutch manager knows Barcelona's De Jong from his time coaching the midfielder at Ajax. The two had success at the Amsterdam side, lifting the Eredivisie title and making it to the UEFA Champions League semi-finals in 2019.JP@JPsalfordStrengths :- One of the best technical midfielders in the world- Elite in the build up phase- Completely press resistant- Sharp 180° turning ( similar to Thiago )- Very progressive from deep- Excellent turn of speed- Sets the tempo- High football IQ- Constantly scans14710Strengths :- One of the best technical midfielders in the world- Elite in the build up phase- Completely press resistant- Sharp 180° turning ( similar to Thiago )- Very progressive from deep- Excellent turn of speed- Sets the tempo- High football IQ- Constantly scans https://t.co/duHcwbGNQzManchester United interested in Matthijs de LigtFrenkie de Jong (left) could arrive with Matthijs de Ligt at Old TraffordAnother former Ajax star who played under Erik ten Hag and is attracting interest from the Red Devils is Juventus defender Matthijs de Ligt.The Dutch centre-back became one of Europe's most admired defenders playing under Ten Hag at Ajax. The 22-year-old made 70 appearances under Ten Hag. He was the captain of the side that made it to the semi-finals of the Champions League in 2019.According to Corriere dello Sport, United are the frontrunners alongside Chelsea to secure De Ligt, who has ran into issues with Juventus over contract talks.Transfer News Live@DeadlineDayLive Matthijs de Ligt want to leave Juventus this summer two seasons before the end of his contract. The Dutchman's representatives and Juve have not reached an agreement over an extension. He could leave for €80M! (Source: @CorSport)2542201🚨 Matthijs de Ligt want to leave Juventus this summer two seasons before the end of his contract. The Dutchman's representatives and Juve have not reached an agreement over an extension. He could leave for €80M! (Source: @CorSport) https://t.co/FUQdGXoyOxDe Ligt joined Juventus from Ajax in 2019 for £67 million and has been a mainstay in Massimilliano Allegri's side since.It seems Ten Hag is eager to rebuild his Manchester United squad with players he has previous ties to with De Ligt and De Jong in his sights.