Mykelti Lefau was still coming down from the high of being drafted when he kicked two goals in Richmond's thrilling upset of Sydney at a raucous MCG.

The New Zealand-born Lefau was once part of Melbourne Storm's development program with dreams of being an NRL star.

But now the 25-year-old looms as an exciting prospect in powerhouse Richmond's rebuild under coach Adem Yze.

Lefau has not looked out of place on an AFL ground after making his debut against Port Adelaide in round three.

The 195cm forward, who once kicked 25 goals in an U19s match, slotted the first major of his career with a banana kick following a free kick in the pocket.

"I''m still just getting over getting on the list," Lefau told AAP.

"It's just been unreal. It's been so fast, but it's just so cool and I'm so grateful to the club.

"Ever since I came to the VFL program (at Richmond), it just felt like home.

"I was a bit iffy if I wanted to continue doing VFL after I left Casey (when the COVID-19 pandemic hit).

"But as soon as I walked through those doors, it just felt like a home, it felt like a family and that's really bringing the best out of me."

Lefau admits he is a "work in progress" but is hungry to keep learning after sitting on the bench for the final quarter in Sunday's win against the Swans.

"When I was subbed off, I was just praying so much 'c'mon boys, pull it off'," he said.

"I can't even imagine what it (the atmosphere) would be like with more (fans inside the MCG), that's not even (close to) capacity.

"We had really good momentum, it's just unreal to do that for him (Yze)."

Yze was rapt for Lefau to kick what he described as one of the hardest first goals anyone could kick.

"I thought put him on the angle ... poor kid, a banana from (15) out," he said.

"But that's so exciting for him to go back, and his first goal is a banana on a 45 degree angle on the MCG in front of a massive crowd.

"He's worked so hard. He's still learning the game, but for him to get some reward by kicking a couple snags on the MCG is terrific."

Lefau is likely to get further opportunities with Richmond's forward stocks being decimated due to injuries to Tom Lynch and Noah Balta on the weekend.