IT WAS one of the more unexpected coaching moves of the season, but one that paid off when it mattered most.

Twenty-four points up at quarter-time and with the breeze about to favour its opposition, Sydney made the bold decision to turn its star forward, Chloe Molloy, into a defender. 

Anticipating the windy weather at Henson Park, Swans coach Colin O'Riordan revealed they had constructed the plan to roll Molloy behind the ball at alternate quarters to effectively intercept any opportunity for the Dogs to score. 

Named as an All-Australian defender in 2018, it's not a wildly foreign position for Molloy but after taking out the leading goalkicker race just last week, the positional switch was still surprising, even if it was successful. 

AFLW expert Kate McCarthy praised O'Riordan for implementing the unconventional move, but criticised the Western Bulldogs for not adapting to equalise it quicker.

"Colin O'Riordan had a plan, and I thought this afternoon he actually outcoached Tam Hyatt," McCarthy said on AFL.com.au's The Wrap.

"He throws his leading goal kicker, the league-leading goal kicker, Chloe Molloy, behind the ball. She had five disposals, three of those were rebound 50s and four intercepts for the term. She's just sitting down there doing whatever she wants, picking off the kicks. 

"Yes, the ball use going inside forward 50 wasn't the best from the Dogs and they weren't able to adapt and change that. But when you've got someone of the calibre of Chloe Molloy sitting inside forward 50 doing whatever she wants, have a look at that."

The Molloy move behind the ball spanned the whole second quarter but took the Dogs until there were just three minutes left in the term before they sent an extra player forward to match up on the Swans star. 

Experienced defender Mua Laloifi, who was predictably matched up against Molloy in the first term, was pulled from her position late in the second to follow her again. 

But McCarthy said the switch came way too late.  

"Three minutes to go, Mua Laloifi comes down and equalizes," McCarthy said. 

"You've wasted almost the entire quarter by waiting for three minutes to go to change that or to do something about Chloe Molloy sitting there on her own."

With the Swans still in leading going into the fourth term and the Dogs kicking with the breeze again, McCarthy said it should have been obvious that O'Riordan was going to replicate the gameplan of the second quarter and pull Molloy back behind the ball. 

But instead, the Dogs left Molloy unattended once again. 

"It's clear Colin O'Riordan is going to roll out the same plan," McCarthy said. 

"Chloe Molloy is clearly going to go behind the ball. It worked once. Why would it not work again? 

"I was really interested to see what the Dogs' plan was going to be in the fourth quarter. Does Laloifi go straight down and take her? 

"We see her line up on a wing and Jas Smith is the winger that's opposing her. That may be not what they planned for, but why are they not changing that straight away? Why are they not rolling Mua Laloifi at the first opportunity they can then play on Molloy?

"Just again she is going to float behind the ball, sit behind the play and do what she wants. She ends up with 12 intercept possessions in this game and essentially takes the game away from the Dogs." 

While the damage was done across the whole match, McCarthy said the second quarter is one of the most damning. With the stats showing the game clearly favouring the Dogs' forward half in the second term, they should have capitalised on the scoreboard. 

"The sheer weight of numbers in their front half, they should have had more to show for it," McCarthy said. 

"[In the second quarter they had] 15 inside 50s to four, 78 per cent time in forward half and 17 intercepts in the forward half to three. And one goal one to show for it? Because you let Chloe Molloy sit in your forward 50 and do whatever she wants and made it really hard for you to score.

"All your ascendancy was for nothing."