The Lisbon outfit managed to hold on to centre-back Lindelof in the January transfer window despite notable interest from United, with the Swede even going on to extend his contract until the summer of 2021 after striking a deal in March.
But United are still keen to tie up a transfer for Lindelof despite his renewed contract driving up his market value to around £50 million, and right-back Semedo is also a target after impressing United scouts on their regular trips to the Estadio da Luz.
And now Goal understands that Vieira is due to land in Manchester on Thursday to accelerate talks between the two clubs, with United keen on tying up all transfer business ahead of their summer tour of the United States which begins with a friendly match against Los Angeles Galaxy on July 15.
United manager Jose Mourinho gave a list of preferred summer targets to executive vice-chair Ed Woodward before heading off on his summer holiday, with Lindelof and Semedo thought to be high on his list as he looks to address some defensive issues which arose during his first season in charge at Old Trafford.
The cruciate knee ligament injury suffered by former Sporting Lisbon centre-half Marcos Rojo has weakened United’s stock in the middle of defence, while Antonio Valencia was the club’s only consistent performer at right-back in 2016-17 and doubts remain over the futures of alternative full-backs Ashley Young and Matteo Darmian.
The 22-year-old Lindelof has made 72 appearances for Benfica since first stepping up from the club’s ‘B’ team in 2013-14, also appearing 11 times for the Swedish national team. Semedo has won two caps for Portugal on the back of 63 first-team outings for the Lisbon side.