She appeared to be having a spot of bother with the oversized, full-skirted gown, which is almost exactly the same as the one Queen Elizabeth walked down the aisle in at Westminster Abbey with Philip Mountbatten, the Duke of Edinburgh over half a century ago.
With one arm encased in the protective case, she was forced to walk across the pavement with the skirt lifted in her other hand.
The brunette actress also had her hair in the same style as the Queen on her wedding day, while her head was adorned with the same sparkling crown and veil.
As well as the bulky blue sling, Claire lifted up the heavy layered skirts to reveal her very modern brown flat boots, which would otherwise be hidden away during filming.
She did, however, remove the sling on her arm as she commenced with the shoot.
It was previously reported that every detail on the monarch’s iconic Norman Hartnell-designed dress – a duchesse satin bridal gown with motifs of star lilies and orange blossoms – would be included in the new version of the dress, to make the occasion look as authentic as possible.
Claire – best known for her roles in Wolf Hall and Little Dorrit – is starring as the royal in the hotly-anticipated new series, alongside Doctor Who‘s Matt Smith as her husband, Prince Phillip.
And Saturday’s filming appeared as lavish as one could expect, with a horse-drawn carriage, two white steeds and extras clad in regal and military costumes all present and correct to bring back to life one of the most famous weddings of the 20th century.
Her Majesty’s wedding in 1947 was presided over by the Archbishop of Canterbury and broadcast by BBC radio to more than 200 million people globally.
So the expensive new TV effort will be hoping recreate the hype, the fervour and the glamour of the big day itself.
Filming for the ceremony has already taken place in Ely, Cambridgeshire – the local cathedral acting as Westminster Abbey – with Claire spotted with eight extras as her bridesmaids.
The series focuses on Buckingham Palace and Downing Street as it follows the story of Queen Elizabeth II from her wedding day in 1947 to the modern day.
Another famous face among the cast is Hollywood star John Lithgow, who has been seen shooting scenes as Sir Winston Churchill.
All the stops have been pulled out to ensure the new Netflix Originals series, spanning 60 episodes across six seasons, is a success.
A reported $100million is being ploughed into the show, which will trace the life of the Queen Elizabeth II from her wedding in 1947 to the present day.
According to The Telegraph newspaper, The Crown will be the most expensive drama ever made by the US streaming company and its first to be made in the UK.
Billed as the ‘the inside story of two of the most famous addresses in the world – Buckingham Palace and 10 Downing Street,’ the series promises a look at the intrigue, love lives and machinations behind the most notable events.
The tagline for the show has a blockbuster ring to it, which promises plenty of excitement, reading: ‘Two houses, two courts, one Crown.’