Manchester United are reportedly desperate to bring either Napoli's Kalidou Koulibaly or Inter Milan's Milan Skriniar to Old Trafford as part of a defensive revamp.
United have won each of their five matches since Ole Gunnar Solskjaer replaced Jose Mourinho as head coach, but the team's defensive issues have been on display throughout the season.
The Red Devils were linked with the likes of Leicester City's Harry Maguire and Tottenham Hotspur's Toby Alderweireld during the summer transfer window, but both ultimately stayed put.
According to The Independent, the two names now on United's list are Koulibaly and Skriniar, with both seen as long-term options for the club.
Koulibaly, 27, is widely regarded as one of the best central defenders in world football and has previously been the subject of a £95m bid from United, according to Napoli president Aurelio De Laurentiis.
Skriniar, meanwhile, joined Inter from Sampdoria in 2017 and the 23-year-old has made 63 appearances for the Italian giants in all competitions.
United have conceded 32 goals in their 21 Premier League matches during the 2018-19 campaign.