Green, who lives in Auckland, said he jumped at the chance to take part in the fundraiser.
"Now that I find myself in a position where I am able to use my influence to do positive things for individuals and communities, I just want to help out as much as I can.
"I was also really impressed at the creativity and drive of this campaign, so couldn't refuse the opportunity to be involved," he said.
"It was also a great excuse to visit the family and bring Matilda down and show her the beautiful Wairarapa."
Although tennis would be Green's sport of choice, for Ms Rice it's netball all the way.
"Matilda loves playing netball, she's the captain of our social team, but I think she's keen for me to teach her a few tennis skills over summer."
Since starring on The Bachelor, Green has found all the attention "a bit overwhelming" but still does not consider himself a celebrity.
"People seem to know a lot about my life now, which is a bit odd, but everyone seems pretty supportive and nice, so it's all good."
He said that, despite becoming "ridiculously busy" after the show, his life had not significantly changed.
"I still do mostly the same things, only now I have a girlfriend."
At Bring it to Colombo, the couple will join other celebrities, including rapper Kaleb "K.One" Vitale, who was originally from Masterton, and former All Whites goalkeeper Mark Paston.
Silver Fern legend Sandra Edge will play the match, along with Wellington-based Central Pulse players Te Huinga Reo Selby-Rickit, Elias Shadrock and Ameliaranne Wells.
Ex Hurricanes prop Bill Cavubati and former Phoenix football player Paul Ifill will be hitting the court too. Thames the police dog will be the event's mascot.
People can bid to play a quarter in the celebrity netball match through a Trade Me auction.
More details for the event can be found on the Bring it to Colombo Facebook page.
