The former Manchester United manager watched Murray's quarter-final victory last year, and the tennis star described the advice he gave him during a 15-minute chat as "gold dust".
Murray said after their meeting last year: 'It's an unbelievable work ethic for such a long period of time. Spending 15 minutes with him, he's a really impressive guy and you can learn a lot from him."
Sir Alex will hope to see Murray continue his fine form at this year's tournament when he takes on South African Kevin Anderson on Centre Court.
Football Association chairman Greg Dyke will hope to forget about England's disastrous World Cup as he is also due to sit in the Royal Box.
He is expected to be joined by entrepreneur Sir Richard Branson with his daughter Holly, singer Elaine Page, Irish golfer Paul McGinley and ex-cabinet secretary Gus O'Donnell.
Meanwhile Murray's fans were forced to queue for more than 26 hours to get a ticket for today's big match.
Just 500 Centre Court seats were available for fans in the famous SW19 queue, and those turning up after the early hours of yesterday morning were left disappointed.
A message on the official Wimbledon website at 8am yesterday read: "There are more people in the queue than Centre and No.1 Court tickets for Monday."
Bookmaker Coral has Murray at 20-1 on to beat Anderson, and just 4-11 to win in straight sets.
The odds have also shortened from 3-1 to 5-2 on Murray winning the title again.
David Stevens, spokesman for Coral, said: "As reigning champion, Andy Murray came into this tournament with an even bigger following than 12 months ago.
"That has been reflected in the number of bets we've taken on him, which in turn has forced his odds down to the shortest they have ever been at the start of the second week at SW19."
Murray's hopes may have been boosted by avoiding any hold-ups amid heavy rain on Saturday.
Cancellations mean fifth seed Stan Wawrinka could face five matches in seven days to reach his first Wimbledon final.
But when Murray was asked if he could stand to benefit from the rejigged schedule, he replied: ''Not really. I've played many grand slams and sometimes the schedule works in your favour and sometimes it doesn't.
''At least they'll have had a two-day break so they'll be completely fresh when they start. It's just bad luck. It happens sometimes.
''I've had situations where the schedule hasn't worked out. You just get on with it.''
The odds are stacked against Murray's fourth-round opponent, Anderson, but the 28-year-old has been relaxing before the big match by learning to play a musical instrument and enjoying a South African barbecue.
"I've been learning how to play the guitar. That's something I enjoy doing. My mum keeps asking me to play her some tunes, but right now I'm just learning all the different notes.
"I've got a travel electric guitar which I take on the road with me. My acoustic guitar is a bit too big so that's at home," he told wimbledon.com yesterday.
After his third-round victory on Friday, Anderson posted a picture of himself on Twitter enjoying a traditional feast with the caption: "A proper South African braai to kick off the weekend right!!!"
Tennis fans at the All England Club today can also look forward to barbecue weather, with the Met Office forecasting "pleasantly warm" conditions at SW19 with a maximum temperature of 22C (71.6F).