The 37-year-old former England international could have become only the third man to play for and against Britain and Ireland's elite if a knee problem hadn't got in his way.
Catt, who toured with the Lions in both 1997 and 2001, had been asked to represent the Southern Kings when Ian McGeechan's Lions toured his native South Africa earlier this year.
With his knowledge of the British and Irish game and having been brought up in Port Elizabeth (the home of the newly-developed Southern Kings franchise), Catt was seen as an ideal candidate to fill the Kings' No10 or 12 shirt in the final warm-up match before the start of the three-match Test series.
Invited by former Northampton and Ulster coach Alan Solomons to head over to the Republic prior to the June 16 clash with the Lions, Catt admits he was more than keen to get involved.
"I was asked to go down and play but, unfortunately, I'd damaged my knee against the Barbarians," said Catt, who would have followed 2009 tourist Riki Flutey and 1955 squad member Tom Reid in playing for and against the Lions.
"If it wasn't for the injury, I probably would have gone down. To be honest, I would love to have done that."
Instead of being in the thick of the action however, Catt was forced to sit at home and watch the Lions from a distance. But, despite the disappointment of missing out on playing his part in yet another Lions adventure, Catt was impressed with what he saw from the tourists.
"I thought the Lions were very, very impressive," added Catt.
"The team spirit this time seemed to be exactly the same as in 1997. That's why they got so close and probably should have won it.
"The pride has been put back into the Lions jersey after it was lost in 2005. A lot of pride was lost then but the Lions is very special thing and fantastic for the game."