The Brazilian, 24, is known for his ball-winning skills in the centre of the pitch, and has developed a reputation as one of Serie A’s most feared tacklers in recent times.
Naturally, the 24-year-old’s showings have alerted a host of big sides, with Juventus, Borussia Dortmund and Wolfsburg all being linked with the player.
However, Chelsea are now also in the running, with a summer swoop a possibility.
Reports suggest that Jose Mourinho is keen on the player, who could provide Nemanja Matic with able cover – the Serbian has been missed when unavailable this season.
Allan is yet to represent his nation at senior international level, but he has played over 90 games for Udinese in Italian football.
Although an able attacking force, his major talent is winning the ball back through tenacious running and fearless tackling.