Moussa Wague has started in LaLiga and the Champions League for Barcelona this term but joined Nice on Friday.
Barcelona revealed two signings on deadline day, Atletico brought in a familiar face, while Juventus' Emre Can moved to Borussia Dortmund.
Former captain Patrick Vieira will forever be associated with Arsenal, but he was not interested in their coaching vacancy last month.
Patrick Vieira insisted he has always been fully committed to Nice, despite being linked with a return to Arsenal.
Manchester United will reportedly resist the temptation to part with Paul Pogba in January, even if the midfielder asks for a transfer.
Former Arsenal captain Patrick Vieira played down speculation of a return to the Gunners after Unai Emery's exit.
Nice coach Patrick Vieira discussed talk he could take over at Arsenal.
Barcelona and Real Madrid are two of seven clubs targeting Bayer Leverkusen midfielder Kai Havertz.
Unai Emery staying at Arsenal could reportedly lead to Alexandre Lacazette and Pierre-Emerick Aubameyang leaving the club.
Chelsea have received acclaim for trust in young players, but how do they compare to the other clubs in Europe's major leagues?