Liverpool and Manchester United to go head-to-head for La Liga defender
The defender has a £44.7m release clause in his contract which Liverpool would be willing to meet.
United are also showing an interest in the 22-year-old, with Ole Gunnar Solskjaer keen to overhaul his defence this summer.
Junior enjoyed a fantastic season with Betis last time out after being promoted from the club's youth ranks in summer 2018.
Junior, who can also play as a winger or even as a central defender, is under contract at Estadio Benito Villamarin until 2023.
However, Betis would be powerless to prevent his departure if Liverpool or United triggered his buy-out clause.