Mitch Brown didn't need long to consider his options when Essendon list manager Adrian Dodoro rang with a simple question two weeks ago. "He said 'Do you want to play?' and I said 'Definitely'," Brown told AFL.com.au.

Before Dodoro's call, Brown had thought little about the opportunity to fill in for Essendon during the NAB Challenge series.

The possibility had barely crossed his mind, even as speculation grew the Bombers would be on the search for top-up players as 25 of their own would sit out the pre-season competition to protect the anonymity of the 17 or so provisionally suspended as the AFL Anti-Doping Tribunal considers its verdict.

The former Geelong key position player had settled into VFL club Sandringham, alongside his brother Darcy. He was fit and healthy and feeling good about his body after injury struggles during his six years at the Cats. He didn't expect his AFL prospects to be soon reignited.

"[The call] came as a bit of a shock, but a good shock," Brown said.

"I rang Paul Hudson, the coach at Sandy, to make sure it was all right and he said it was too good an opportunity to pass up. Then I went and spoke to Essendon and said it was all fine."

Brown is one of seven recently delisted players the club has signed on short-term contracts as replacements ahead of Saturday's clash between Essendon and St Kilda at Morwell.

The appeal to join the club, even if only for two weeks, was obvious to the 24-year-old.

"I was speaking to a few of the other boys and it's a good chance to show that we can still play at that level," he said.

"And we're training with Essendon every day pretty much, so it's something we can show them as well."

Brown stepped into the club's facility on Wednesday last week, and trained alongside the VFL squad.

On Friday, he completed his first session with the AFL-listed players, having known nobody apart from former Cats teammate Paul Chapman and Sandringham teammate (and ex-Saint tagger) Clint Jones, another short-term recruit.

"It was a little bit daunting at the start but the boys have been really welcoming and I've enjoyed it. I was speaking to a mate the other day and I was saying how it's been a whirlwind couple of weeks," he said.

"It's definitely a different situation, but it's been good. Obviously we've had to learn the game plan in about a week, which has been a bit challenging, but we've pretty much got the basics of it right now.

"Because it's going to be a pretty young team on the weekend, there's a few of us who have been around the system a while so it's about trying to help the younger guys and try to lead by example."

Brown expects to play in defence for the Bombers, having been swapped from end to end in his time at Geelong.

Versatility was one thing he learned in his 15-game career with the Cats, with plenty of other lessons while there alongside some of the competition's standout players.

"I'll try to use that in my next couple of games and hopefully show my worth," Brown said.

"It was obviously disappointed to get delisted, but I guess I have to show what I can still do. Whether that be in the Essendon team in the next few weeks or just at VFL level where I can try to get my name back up there."

Brown's out-of-the-blue AFL chance has meant he needs to juggle some other things in his life. Recently he enrolled in a teaching course at Melbourne's Deakin University.

That's meant to start next Monday, but he will probably be busy in a training session, or in a game review meeting, when classes begin. "I've got to work that out," he said. "I might have to do it part-time."

Brown isn't sure how long that adjustment will need to last. He is contracted for several weeks, but with no date set for a final judgment in the anti-doping hearing, it could be longer.  

"I'm very excited to get out there, obviously it's a bit different to be playing with some new teammates but they've been really good and I definitely think we can have a crack and have a win," he said.

"I'm just concentrating on the next three weeks where they've pretty much said that we're playing. After that is an unknown."