WATCH: Stars take the plunge for Big Freeze

LLEYTON Hewitt had always dreamed of gracing the MCG in Adelaide colours, but plunging into a pool of icy water wasn't exactly what he had in mind.

The former world No.1 tennis champion was among a host of sporting greats who took the plunge at Monday's third Big Freeze fundraiser.

More than $2 million was raised for motor neurone disease research leading up to the Queen's Birthday clash between Melbourne and Collingwood.

Former Essendon captain and Melbourne coach Neale Daniher is suffering from the fatal disease and has become the very public face of the fight against MND.

Retired Test opener Adam Gilchrist took the honours for most creative outfit as "Shane Warne's flipper", wearing the legspinner's green and gold uniform over a dolphin outfit.

Champion marathon runner Steve Moneghetti wore a Cathy Freeman-inspired bodysuit, while basketball champion Andrew Gaze dug up the outfit he wore as flag-bearer at the Sydney Olympics.

Former Australian netball captain Sharelle McMahon meanwhile showed she hadn't lost her touch, shooting a hoop on her first attempt while still submerged in the icy water.

But the biggest cheer was reserved for Hewitt, who handed his Davis Cup jacket to Daniher, revealing a Crows guernsey underneath.

"As a young kid growing up, as a tennis player, you always wanted to get a gold jacket and represent your country in Davis Cup," he said.

"For everything Neale's done for this, and the whole community, especially around Australia, I just want to give Neale my jacket. So thank you mate."

Hewitt's tennis accomplishments have made him one of Australia's most beloved sporting champions but the Crows fanatic couldn't help but reflect on the AFL career that had eluded him.

"We talk about tennis being a dream for me but it was always a dream to wear the tri-colours of the Adelaide Crows at the MCG," Hewitt said.

"This is about as close as I get."

Daniher's daughter, Bec, works closely with her father to increase awareness of and lobby for greater research into the disease.

"(The Big Freeze event has) grown beyond anything we thought possible," she told 3AW on Monday.

"Seeing the general public and football public get together and have this game filled up to the brim and have our donations rolling through is incredible.

"It's really important someone stood up. Before, it was a bit faceless, the disease, and you need a face out there who's going to push it, get the media involved (and) get the public involved.

"Neale's been that person and you can see the changes we've been able to achieve in just two-and-a-half short years – we've got three clinical trials and eight research projects, where before there was absolutely nothing."

The Federal Government will match whatever is donated to the cause, including at the game and online at https://fightmnd.org.au/

AFL CEO Gillon McLachlan joins Neale Daniher for the walk to the 'G. Picture: AFL Photos

Olympic Gold medallist Alisa Camplin slides down. Picture: AFL Photos