As the James Bond theme boomed around the stadium, the proud Scot was given a standing ovation while watching tournament favourite Roger Federer taken on little known American teenager Frances Tiafoe.
Big Tam, who starred in seven Bond films between 1962 and 1983, certainly looked engrossed in the action as he watched from his seat in the President Box at the Billie Jean King National Tennis Center.
The 87-year-old Edinburgh native was looking great in a smart black blazer, pullover and navy trousers.
And the proud Scot, who has retired from acting, gave a nod to his roots by wearing a distinctive green tartan bunnet, which he took off after taking to his seat.
Fans were certainly excited to see the former milkman there, with one tweeting: 'Got to love it, Sean Connery still going strong at 87, out to watch the 007 of tennis, Roger Federer at the #USOpen tonight.'
Another said: 'Sean Connery is at the @usopen tonight! They played the Bond theme for him. Got as much applause as Federer.'
Over the course of his career he has been lavished with honours, including being named The Greatest Living Scot, Scotland's Greatest Living National Treasure, and In 1989 he was even named the Sexiest Man Alive by People magazine.
But Sir Sean, who is worth an estimated $350 million, has also been criticised in the past for funding the Scottish National Party while living in the Bahamas.
But in 2003 he revealed he had paid £3,694,591 in UK tax between the financial years 1997/98 and 2002/03 in a bid to quell the criticism.
The former coffin-polisher said at the time: 'I'm an easy target because of my political opinions.
'But I defy anyone in Scotland to find one detail where I knowingly ever did anything that was to the detriment of Scotland. It gets up my nose.'
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