By Matthew Cooper Manchester United could be banned from playing in Europe next season following Sir Jim Ratcliffe’s purchase of a minority stake in the club, according to reports. Ratcliffe also owns French side OGC Nice, who currently sit fifth in Ligue 1, and UEFA’s rules on multi-club ownership mean they would not be allowed to compete in the same competition. UEFA have changed their rules slightly, allowing clubs under common ownership to compete in different European competitions as of next season, but the ban on those teams playing in the same tournament remains. “It is correct that Man…