The ex-Adelaide Crow was the first player signed by a fledgling Giants in 2011 and has been a key pillar of the club's first decade, both defensively and in a leadership capacity.

His re-signing follows that of superstar small forward Toby Greene, who penned a record six-year extension last week. He and Davis were the two most high-profile GWS players off contract this year, and their decision to sign the dotted line before round one only strengthens Davis's opinion that the Giants are closing in on their first flag.

"As more and more time goes by we don't get younger but in saying that, a large core of our group are 23, 24 so I think we've got a pretty good window ahead of us," Davis said.

"For me personally there's always going to be pressure because I want to win one before I retire. You ask all the boys here that's why we're here – we want to be successful."

"Even from the early days when we probably weren't winning a lot, the blueprint was there for some opportunities where we might be able to get to the pointy end of the season.

"That's shown the last two years we've been able to get to preliminary finals, one home and one away. Unfortunately I haven't been able to obtain it [success] yet but that's definitely a lure for why players want to play [at the Giants]."

Young defender Isaac Cumming was also granted an extension until 2020 on a busy day for the club during which gun midfielder Dylan Shiel copped a heavy head knock when he collided with Matthew de Boer at training.

A stretcher was carried onto the field as Shiel was assessed for a neck injury, but he was able to leave the training ground without assistance.

Davis admits he took a massive gamble in 2011 when he opted to sign with the Giants after establishing himself as a young key defender in Adelaide.

The Crows' hierarchy were left disappointed when their 2008 round-one draft selection announced he was leaving the club after just three seasons, but it was an opportunity Davis simply couldn't pass up.

"I'm very happy with the 20-year-old self for doing it," Davis said.

"It's definitely the road less travelled compared to if I just stayed in Adelaide and stayed in my comfort zone.

"It's also opened my eyes up to a lot of different things, a different lifestyle, a lot of different opportunities that I wouldn't have got in Adelaide. It was a pretty brave call back then but I think I made the right one.

"I was pretty bullish when I signed, probably more from an on-field point of view I knew the list build that we were going to have. I knew if we could retain talent along the way we'd have a very talented side.

"I didn't have a picture of how big the club could be in terms of its impact on a community and I think we've made a huge improvement here. You look at the statistics in terms of participation of AFL in the western suburbs of Sydney since we've started, it's just astronomical improvement and that's something I didn't really comprehend when I started and made that decision.

"The on and off field benefits that I've been able to see have been enormous in seven years since I've been here."