Casey played in Europe’s successive nine-point victories in 2004 and 2006 – famously ending one match at the K Club with a hole-in-one – as well as the defeat at Valhalla in 2008.
But he was then overlooked for a wild card in 2010 by captain Colin Montgomerie, despite being ranked seventh in the world at the time, and was not even a member of the European Tour for a number of years before rejoining in 2017 and getting a wild card the following year in Paris.
“There was a time pre-Paris that I thought I might never play another Ryder Cup, having missed a couple, more than a couple,” said Casey, who qualified automatically for Padraig Harrington’s team.
“I was quite emotional in Paris because of that gap. The form I had been through and to be part of that great team in Paris has been one of the most special moments of my career.
“The fact I was a pick made me sort of nervous coming down the last few weeks. This one I felt much more comfortable.
“And now I’m even looking at Westy (Lee Westwood) going, ‘How many more can I play? I think Westy is 48. I’m 44 thinking can I squeeze a couple more out?
“It’s amazing how my view on it has changed going from maybe I’m done, to what does the future hold?”
A United States team featuring eight of the world’s top 10 are odds-on favourites to regain the trophy after their comprehensive defeat in Paris, but Casey is quietly confident the visitors can pull off another upset victory.
“I think firstly the dynamic is brilliant,” the 44-year-old added. “I don’t like to compare teams and say this team is better than another team I’ve played on. But this team as a unified team is so strong.
“I’m proud to be standing next to my 11 team-mates and captains and vice-captains. We have such a unified team going and Paddy has been a major role in that because you can have brilliant teams and maybe be slightly rudderless.
“But I’ve been utterly impressed with Paddy’s captaincy. His communication skills have been top-notch and a relaxed air to everything we do, but a serious approach at the same time.
“We tend not to say what goes on behind closed doors but this is my fifth (Ryder Cup). It gets better and better every single time.”