Retiring Brisbane captain Emma Zielke knew before last week's preliminary final win over Collingwood that a premiership on Saturday would signal the end of her AFLW career.

The 32-year-old told coach Craig Starcevich she would retire on 41 games if the Lions made it into Saturday's NAB AFLW Grand Final – but only if they won it.

"I said, 'If we win, I'm out'," Zielke said, after their 18-point win over Adelaide.

"It was a fairytale ending. The decision was made for me."

Zielke admitted she didn't know what she would have done if the Lions had lost their third Grand Final and was glad she wasn't in a position where she had to find out.

Instead, she gets to leave the game on the greatest high possible; a premiership captain after three attempts.

"I just thought I would go out while I was still playing alright footy and keep my pride intact and not get dropped," she said.

"It was getting too much for the old body."

Zielke finished the game on the bench after she suffered a high hamstring strain – the first in her life – in the opening contest of the third quarter.

She tested it out in an attempt to return to the field but said she had lost all power in her right leg.

The image of her sitting on the bench distraught as her team attempted to pull away from the Crows summed up how much the game meant to her.

She said she quickly made peace with her fate as the Lions moved to a 22-point lead at three-quarter time and was philosophical about the severity of the injury given she won't play again.

"They put ice on it and I was like, 'You don't really need to'," she laughed.

"I have to get a scan but I don't really need to.

"It's just old age, trying to keep up with the young ones."