Rather than tries and drop goals, touchdowns and home runs were scored in American football and baseball games.
American GIs brought sports from their homeland to Ravenhill in the early-1940s, drawing thousands of spectators.
Now, the Public Record Office of Northern Ireland (PRONI) has merged photographs from the games with shots of the modern day Kingspan Stadium.
Garreth Montgomery from PRONI uncovered the original images that showed how the ground was used during World War Two, and considering them to be unusual, he decided to blend the old with the new.
"We have a very large collection of old glass plates and negatives taken from across the north in the archives at PRONI," he said.
"I'm interested in anything to do with rugby and Ravenhill, and I came across these rare shots of American GIs playing there."
He visited the Belfast rugby ground - now known as the Kingspan Stadium -  and took new photographs at the same locations where the originals had been taken.
Mr Montgomery said it was then a case of lining up and merging the photographs using some computer trickery.
"It does take quite a bit of time to do, it's a labour of love," he added.
The new images are the latest in a series released by PRONI showing Northern Ireland landmarks in both their past and present form.
Mr Montgomery has previously created images showing Belfast City Hall, Carrickfergus Castle in County Antrim and Donaghadee Lighthouse in County Down, among others.
"I am always on the lookout for interesting old photographs that could be merged with contemporary digital shots," he said.
"An awful lot of people remember those days and the photos show how much things have changed but at the same time how a lot of similarities remain."
More will be released in the coming months, he said.
Do you have any memories of the American football or baseball games between US soldiers that took place at Ravenhill or any other sports grounds in Northern Ireland? If so, please email us at bbcnewsni@bbc.co.uk.
A whole new ball game was being played at the home of Ulster rugby more than 70 years ago, new archive images show.