Twelve years and nine months, four delistings, two clubs, 100 games.

Sam Reid has taken more detours than most on the journey to his ton, but the GIANTS defender will finally reach the milestone when he lines up against North Melbourne on Sunday.

Only six players in VFL/AFL history have had to wait longer than the 4671 days it will take from Reid's debut in round 22, 2008 to joining the 100 club, and none have waited longer in the past 93 years.

"I've been trying not to think about it too much. We've got a main session [on Thursday] to go and I've got to get through that," Reid said with a smile on Tuesday.

"The way my career has gone, the ups and downs over 14 years, I'm really happy that I've got there for my family and just myself for the perseverance and everything that I've shown to get to 100 games.

"It's a pretty big milestone. Obviously it has taken me ages but I'm pumped to get there."

Reid was first drafted by the Western Bulldogs in 2007 and played 10 matches with the club. He then joined the GIANTS as an uncontracted player for their first two seasons in the competition, playing 14 matches before persistent shoulder injuries forced him into early retirement. 

The 188cm defender moved into a development role at the GIANTS with a view to building his coaching credentials, while also playing in and captaining the NEAFL side.

But Reid jumped off the coaching path after kicking 54 goals in his two years in the NEAFL led to him being re-drafted by the GIANTS in the 2016 rookie draft.

Reid played 19 games in his second stint with the GIANTS before being delisted and re-drafted again at the end of the 2017 season. He was delisted for a third time by the GIANTS at the end of 2020, but was again re-drafted as a rookie.

"[The milestone has] made me think about what my journey has been like, the resilience I've shown to have two years out of the game, come back, the injuries I've overcome, played with type 1 diabetes, I'm pretty proud of myself to be honest," Reid said.

"I get satisfaction out of proving people wrong and Leon [Cameron] wouldn't mind me saying that I really wanted to prove him wrong. He was the one that came to me and said I might have limited opportunities.

"But when I came back, I wanted to give it a fair crack and six years later I'm still going around."

The 31-year-old has been on multiple one-year deals at the GIANTS except for a period where he had a two-year contract.

Reid has used the uncertainty over his future as extra motivation throughout his career, though admits it has also meant plenty of anxious moments including late last year when he was the last GIANTS player to be offered a new deal.

"I get delisted every three years because you have to come back on, so I've got a record there. That's part of my story and resilience and everything that I've shown," Reid said.

"The way that I play and the role that I play in this team, as that shutdown defender who plays life or death footy, and tries to set the example there, I think [a one-year deal] keeps me on the edge.

"Every year I'm playing for another year and a contract. But living on the edge is what I do at the moment and I enjoy that because every game I have to treat like my last."

Reid has only lined up in 10 matches or more in a season three times, all in the 2017-19 period when he played 60 games.

That included all 26 matches in the GIANTS' run to the 2019 Grand Final, as one of only four players to play every game for the year.

Perhaps unsurprisingly, Reid looks back on that season and finals run as the highlight of his career.

"Obviously the [Grand Final] day didn't go the way that we planned, or would've liked," he said.

"But I had my first kid that week, Elijah, after the prelim against Collingwood. I had two hours sleep in about 50 hours.

"It was a good time and I look back on those as good memories, and that year was definitely the best year that I've had."