The emerging forward had to put his doubts aside and board a plane for Melbourne shortly after he learned he had been drafted by the Roos at pick No.69 in the NAB AFL National Draft of that year.
When he walked into Arden Street for the first time, he was put at ease pretty quickly. A familiar face from his days as a junior footballer with the Aspley Hornets in Queensland stood out, and softened some of the first-day nerves the youngster was experiencing.
"Daniel Pratt used to hand out our jumpers at our jumper presentation when we were juniors, so I knew of him pretty well and I grew up playing with his brother, but I only first met him here," Warren told kangaroos.com.au.
"His dad used to coach me so I know the family pretty well."It was good to have a connection with someone."
Pratt wasn't the only one Warren knew when he arrived at North Melbourne. He also had a pre-existing connection with fellow Queenslander Gavin Urquhart, who was recruited at pick No.22 in the same draft.
Having two familiar faces at his new home helped Warren get through his first year, which he remembered as being "all about adjusting".
"In the first year, because I was only 17, it was a big growing up year for me," he said.
"I've definitely settled in and it's like home for me now. I love it."
After spending some developing years in the VFL, Warren broke through for his debut match two weeks ago in the Kangaroos' round four win over Essendon.
The 20-year-old said an improvement in his consistency had been the main reason for his promotion.
"I don't think it has been a finger-snap change. The last two years I've been working up to this point," he said.
"I've been trying to persist with playing good footy. I had a good pre-season this year and was lucky enough to get a couple of lead up games in the NAB Cup and Challenge. That all helped.
"It's been a joint effort from a lot of people to get me here. In the forward line, Drew Petrie has helped me with setups, and Adam Simpson is always giving me advice and has always been a great role model.
"Growing up playing at the same club 'Pratty' played at has meant he's always been there for me over the last few years as well, which has been great."
Warren said the past two weeks had produced another necessary lesson in his development as a professional footballer, having encountered a rollercoaster of emotions.
"It's been pretty amazing. I was on a high after the first weekend after the win over Essendon and now I've seen the contrast this weekend with the loss against Richmond," he said.
"But I'm just happy to be in the side and keeping my spot and hopefully contributing a bit along the way."
