4) Marquinhos (Paris Saint-Germain)
Marquinhos has been linked to Barcelona several times in the past, even before he signed with PSG. The youngster has found it hard to break into the back four of PSG, with the Brazilian Thiago Silva and his countryman David Luiz forming an incredible partnership at the heart of the defence.
The young Brazilian was visibly disappointed in being dropped from the champions league quarter-finals against Manchester City which ended 2-2. Marquinhos can play as a right-back and a defensive midfielder too. He is fast and has a good sense of positioning too.
The former Roma defender is strong and has superb ball playing skills. Marquinhos is one of the most promising hot prospects in European football today with several clubs vying for his signature.
Barcelona will possible struggle in replacing veteran defender Mascherano, who has similar capabilities and size but the PSG defender is the perfect replacement for the former Liverpool player.
Though the Brazilian is excellent, his age makes him more expensive as he is considered one for the future. Only a bid upwards of £35 million is going to make PSG want to let the youngster go.