Saul Niguez
Chelsea also need to look at their defence and they could try to sign this gem of a player from Atletico Madrid. Talking about the connections with Diego Simeone, Saul is the perfect person for all this. The 21-year-old can play both in central defence and in midfield and that would work well for the Blues.
Instead of targeting someone like a John Stones, Chelsea should try to sign Saul and with him spending a bit of time in England, who knows he could become the next big thing for the Blues.