The actor couldn't believe his luck when the "Transformers" star, who is considered one of the world's great beauties, started showing him some interest when he guest starred on her TV show "Hope and Faith" - but he talked himself out of a date with her, because he thought he was simply misreading the signs.
"She was really young and I was like, 'This isn't this. This can't f***ing happen. This isn't going to happen, no way,' " he said during an appearance on Barstool Sports' KFC Radio podcast on Thursday (August 15). "I left and she was just really persistent - and thank God."
Plus Green had just "gotten out of a relationship" and wasn't looking for anything serious at the time. But that all changed when Megan told him she was tired of chasing him and planning to move on.
"That's when I realised... 'I must be really into this situation... the thought of that kills me,' " he added. "And... we've been together now for 15 years. You know, it's funny because you talk about Megan now because you know her after all of that. But, you know, this was when I met her... pre-Transformers. It was pre- all that."
"(There was) so much anonymity going around... It was really easy and fun."
The couple started dating in 2004 and became engaged in 2006. They called off their relationship in 2009, but reconciled and wed the following year.
They now share three sons, Noah, Bodhi, and Journey, aged from six to three. Green is also dad to 17-year-old Kassius, his son from his relationship with ex-girlfriend Vanessa Marcil.