ZAC WILLIAMS was happy to tell anyone and everyone in Greater Western Sydney's victorious room after Saturday's stunning win over Collingwood.

"I've been telling you all for seven years that I'm a midfielder!" he said with a laugh.

Williams played a massive role in the Giants' 47-point triumph but not in his usual role as a dashing half-back.

The 24-year-old was used as an onballer by coach Leon Cameron and racked up 26 possessions, 10 tackles and five inside 50s.

Williams play fighting with Stephen Coniglio during training. Picture: AFL Photos

In the absence of midfield staples Josh Kelly, Stephen Coniglio, Callan Ward and Matt de Boer, the contribution of Williams came at a perfect time.

It's not the first time Cameron has used his attacking defender in the midfield, but with so many stars out, Williams told the extra responsibility wasn't lost on him in the lead-up to the Magpies clash.

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"Leon called me into his office during the week and told me I was going to start on the ball and I was pumped to have a crack inside, but also a bit nervous," he said.

"But the other boys backed me in right from the start so that helped me a lot.

"Especially Jacob Hopper and Tim Taranto, they've been absolute superstars from the beginning of the year, they're absolute bulls, and I can't give them enough credit for what they've done."

Williams isn't sure if last week was a short-term fix, but with Kelly not due back for at least a fortnight, Coniglio and de Boer out for the home and away season, and Ward gone for the year, he might have to get used to his new position.

The Giants do have highly rated youngsters Jackson Hately, Jye Caldwell, Aiden Bonar and Nick Shipley available if Cameron does decide Williams is needed in defence, starting with Saturday night's road game against Port Adelaide.

"All through the pre-season I made sure I'd stick my head into the midfield meetings just in case I got thrown in there, because I know Leon likes to have that option," he said.

"I'm happy to stay in there or return to half-back, wherever the team needs me the most.

"We've got some young boys playing good footy in the midfield, so if I get pushed back for one of them to get an opportunity I don't mind."

The Giants' win over Collingwood halted a worrying three-game losing skid and reinvigorated their top-four hopes, but Williams said despite the form slump, the players never lost their belief.

He said the team must now maintain the standards they set against the Pies for the rest of 2019.

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"People wrote us off but we just had to block out all the external noise and focus on what we could control," he said.

"We hit a bit of a rough patch, but the coaching staff hit the nail on the head with their messaging.

"They told us we've had our slump, so we just need to go out and control what we can control, and that’s tackling hard and putting pressure on the Pies and making it a really strong contest.

"All 22 players played their role to perfection.

"As long as we come in each week and focus on tackling and being hard at the contest, that will hold us in good stead."