Ferguson was among the many paying tribute to former England captain and manager Kevin Keegan, whose illustrious playing career took him to Scunthorpe United, Liverpool, Hamburg, Southampton and Newcastle.
During six seasons at Liverpool from 1971 to 1977, he won three league titles, the European Cup, two Uefa Cups and the FA Cup.
He later lifted the Bundesliga with Hamburg and secured back-to-back Ballons d’Or in 1978 and 1979, remaining one of just four English players to have received the honour.
As a manager, his career also included spells in charge of Fulham and Manchester City, as well as England and Newcastle.
Keegan brought Alan Shearer to Newcastle in 1996 for a then world-record £15m fee and later led England while the striker captained the national team.
Shearer called him a close friend, admired by everyone for his passion, energy and, above all, his friendship, saying Keegan loved football and Newcastle more than anything.
He added that he felt privileged to have known Keegan and that he will be deeply missed.
Newcastle United head coach Eddie Howe reached out to Keegan after taking the Magpies job in 2021.
Howe said Keegan inspired him as a young player and, in recent years, offered friendship, guidance and support that meant a great deal.
He spoke of Keegan’s remarkable warmth and generosity, noting that despite all he had already done for the club, he immediately made Howe feel welcome.
Howe added that Keegan understood the privilege and responsibility of leading Newcastle United and was always ready with wisdom, encouragement and support.
Former Scotland and Liverpool star Sir Kenny Dalglish hailed Keegan as one of his generation’s finest, saying he wore Liverpool’s iconic number seven with great pride and distinction.
Dalglish, who arrived from Celtic in 1977 to replace Keegan at Liverpool and later followed him as Newcastle manager, said Keegan’s on-field achievements were outstanding and that he was also a wonderful person and true gentleman.
He credited Keegan with giving supporters countless cherished memories and leading teams that played a brand of football fans loved.
Dalglish concluded that the sport has lost a genuine great.