If it wasn't for Tom Lynch tweaking his calf in the warm-up, Hugh Greenwood would've been watching Saturday night's clash against Greater Western Sydney from the grandstand.

Instead, Adelaide's accidental hero leapt high into the night sky, plucked the ball from the heavens and slotted a crucial goal to help the Crows to their most significant win of the season.

Greenwood's goal at the 25-minute mark of the last quarter gave the Crows an eight-point buffer they never surrendered – getting home 12.10 (82) to 9.7 (61) – against one of the premiership favourites.

The 27-year-old finished with just seven disposals, playing in an unfamiliar role as a third tall forward, but he made an impact when it mattered.

Greenwood was told just 10 minutes before the game that he was playing after Lynch injured his calf in the warm-up.

"I had my feet up, was just hanging out and messing around, and next minute, Lynchy was done and I had about 10 minutes to get ready," Greenwood told AFL.com.au.

"I'm not the quickest person to get ready – my feet are completely taped – so it was real late notice, but thankfully I did enough to prepare.

"I was on the loo reading my notes because I missed out on the team meeting.

"I was just trying to go through a normal pre-game prep in a condensed time, and thankfully it all worked out."

INJURY UPDATE: Lynch's late withdrawal

Greenwood was the second emergency in line to play, behind veteran David Mackay, and was there as cover for tall forwards Lynch, Taylor Walker or Josh Jenkins.

His moment came in the last quarter when a high ball came into the forward 50 – Greenwood using his athletic prowess to leap high and take what co-captain Rory Sloane described in the change room as 'a hanger in the goal-square'.

Sloane's distance was a little out, but Greenwood went back and slotted the goal from about 30m.

Post-game, Greenwood admitted his set-shot mistake in the Showdown, where he kicked into the man on the mark, was on his mind as he lined up for goal.

"I hadn't had a shot on goal since I kicked into Paddy Ryder a few weeks ago, so it was better than a few weeks ago," he said.

"It's been on my mind the whole time.

"I turned around right away and checked where the man on the mark was."

TRIO SIGN: Young Crows recommit

Greenwood was stiff to be dropped from the side after last weekend's thrilling two-point win against Melbourne in Darwin after picking up 20 disposals.

But an almost fit list – with 43 of a possible 44 players available – meant he was squeezed out of the side.

"I had a couple of sleepless nights going over what I can do to get back in the side and what I wasn't doing to get dropped," he said.

"I just know I'm not one of the bigger players on a magnet.

"I've always been a role player and that's what I did tonight – tried to tackle, tried to fly – that's why they put me in."