The former Reds boss was one of a number of high-profile football figures to attend Sir Bobbys memorial service held at Manchester Cathedral on Monday, with around 1,000 guests invited.
Former player and boss Ole Gunnar Solskjaer, ex-Manchester United chief executive David Gill and current United players Tom Heaton, Jonny Evans, Harry Maguire and Luke Shaw were all in attendance. Heroes of former years including Roy Keane, Peter Schmeichel and Paul Scholes were also present as were Prince William, UEFA chief Aleksandr Cerefin and England manager Gareth Southgate.
During the procession of Sir Bobbys coffin, the hearse passed by Old Trafford as thousands lined the streets to pay their respects to the 1966 World Cup winner, who died aged 86 last month.
Among those to speak at the service was Gill, Manchester United Foundation CEO John Shiels and grandson William Balderston. Sir Bobbys wife, Lady Norma, followed behind the coffin when it was carried out of the cathedral.
After the service, Sir Alex spoke to reporters about his emotions and gave a touching tribute to Sir Bobby himself. It was a very sombre occasion, obviously, he said, as per the BBC.
Sir Bobby Charlton – thousands gather to say farewell to Manchester United legend in pictures
The speakers did fantastic, particularly his grandson was magnificent. Its not easy to get up and speak, particularly with such a person as his grandfather. Bobby Charlton was a wonderful, humble man. And Im at Manchester United because of Bobby Charlton, without a doubt.