The Leicester Tigers flanker, who toured South Africa in 2009, suffered a career-threatening neck injury a year ago.
He returned to action in January, following eight excrutiating months on the sidelines, and never thought he would be back in contention for the trip Down Under.
But he was thrilled to be named as one of six Tigers in Warren Gatland's 37 man squad alongside Manu Tuilagi, Dan Cole, Tom Youngs, Ben Youngs and Geoff Parling.
"It is just unreal," said Croft.
"A year ago I broke my neck so, to be able to come back and be selected for the Lions, is just a fairytale, without sounding too cheesy and corny.
"It hasn't sunk in. I'm absolutely ecstatic. And I am made up that I've got my mates along with me this time."
Croft wrote off his chances in March but a spell of outstanding form impressed the Lions selectors enough.
"When I said that, it wasn't an attempt to be modest," said Croft.
"I genuinely never thought I would be in contention. I came back playing at the end of the Six Nations and was still trying to find my feet."
Croft has fond memories of his trip to South Africa in 2009. He was only a late call-up following the suspension of Alan Quinlan but became one of the stars of the tour, with two tries in the first Test.
And he hopes to implement that experience when he jets Down Under next month.
"Hopefully, I can take some of that experience," said Croft.
"But all the guys selected have massive experience in Test-match rugby, playing in huge games and World and Heineken Cups. No-one will be out of their depth."
And the athletic flanker was delighted to get the nod alongside so many of his club-mates.
"It just shows how well the club looks after its players and the types of characters it brings through," he added.
"Look at Tom Youngs and how well they have brought him through from centre to hooker.
"He is now the club's starting hooker, England's starting hooker and a Lions tourist.
"And who would have thought that skinny guy Geoff Parling from Newcastle would play for the Lions? He absolutely fully deserves a call-up, as do the rest of the boys."