All good things must come to an end.

And when Jonathan Brown announced his retirement on Monday, it marked the end of one of the truly great careers at the Brisbane Lions.

But as one door closes, another one opens – and that certainly seems to be the case for young Lions defender Daniel McStay.

McStay is set to line-up in his first ever senior AFL match just days after watching one of the all-time greats of the Club hang up his boots.

The symmetry between Brown’s end and McStay’s beginning will be something the 19-year-old can carry with him throughout his playing days and into the future.

Even if it has only been for one season, McStay will benefit greatly from having trained alongside the future Hall of Famer, but now has an opportunity to step out from the shadows and help build a new era at the Lions.

Recruited from the Eastern Ranges with Pick No.25 at the 2013 AFL National Draft, McStay had realistic expectations as he approached his debut AFL season.  

“Being a key position player it's obviously a lot tougher to break out in your first year of AFL footy, so I'm planning on just getting on the training track and doing everything possible to improve and work on my deficiencies, and just become a good NEAFL player if that's possible,” McStay said early in 2014.

“The plan is basically to stay injury free for my first year and take it from there I guess.”

Just five months later and he’ll get his first taste of senior this Saturday night against North Melbourne.

At 194cm, McStay is more of a hybrid defender who is capable of playing tall or small.

He even spent some time up forward lately in the NEAFL as part of the development process, and could very well prove to be a valuable ‘swingman’ in the future.

He becomes the sixth member of the Lions’ 2013 National Draft class to make his senior debut in 2014 – and eighth overall at the Club.

McStay will also become the first player in more than six years to don the No.25 guernsey in a senior match with the Lions.

Not since Round 4 of 2008, when Wayde Mills represented the Club against Port Adelaide at Football Park, has the No.25 seen senior action.

Its past two owners – Bart McCulloch (2009-11) and Richard Newell (2012-13) – didn’t play a senior match.

Please find below a full list of players to have worn the No.25 with the Lions (Fitzroy and Bears included), and their games in that jumper: