The Glasgow Warriors player has been included in the 23-man party to face the Wallabies in the opening Test of the series on Saturday.
However, Maitland admits that he wasn't even contemplating a call-up to the Lions until a few months ago.
"It's been a crazy 12 months," said Maitland. "As I've been saying, it's been a rollercoaster ride for me and it's pretty crazy where I am, playing the Wallabies and on the pitch for the Lions. It's an honour and it's been a whirlwind. [The Lions] never really entered my mind until after the Six Nations. It just happened to be a Lions year when I came over to Scotland.
"It takes me away sometimes when I think about it, I have to pinch myself to realise what I've achieved in a short amount of time. I am very lucky and things have gone well for me. I have to pinch myself because this is crazy. Seven months ago I was still a grass-roots player and now I'm playing against my old coach [Robbie Deans].
"There's been a massive rivalry with Australia growing up so it's going to be crazy. It's going to be a really tough game, we know that, and it's going to be a hell of a spectacle."
The Lions face the Wallabies in Brisbane at 11.05am on Saturday.