Chelsea and Aston Villa are hoping to take advantage of a financial squeeze at Sevilla.
The Spanish side finished fourth in LaLiga and went unbeaten for almost four months but may now struggle to keep their side together.
Chelsea are eager to sign French centre-back Jules Kounde while Villa have rekindled interest in their Brazilian defender Diego Carlos.
The Spanish side are resigned to selling key players this summer to balance the books and that could mean Chelsea landing £70million-rated Kounde for closer to £50m while Villa could prise away £40m-rated Carlos for around £30m.