Greater Western Sydney's potent forward line holds no fears for Callum Mills and his fellow backmen at the Swans.

Sydney's defence was the best in the competition last season but is ranked 13th heading into round five, with their disposal efficiency coming out of the back 50 a massive problem.

They'll need to find a way to put the shackles on the Giants, who have the third most points in the competition after four games. And stopping one forward won’t be enough for the Swans. Toby Greene, Jeremy Cameron, Devon Smith, and Jonathon Patton have all booted three or more goals in a game this year.

Mills said that while GWS had plenty of forward firepower, he's not sure about it being labelled the best in the competition.

"They're definitely a good forward line, but I don't think you can look past us or Adelaide, it depends who’s on their game on the day, really," Mills said.

Mills, last year's NAB AFL Rising Star winner, is a chance to get the job on Greene in Saturday's Sydney derby at the SCG. 

"He's (Greene) a great player and, credit to him, he's been playing well for a couple of years now.

"He's a really dangerous player that we're going to have to keep an eye on."

Mills backed the senior Swans to lift against the Giants, and said the promise shown by the team's younger players under enormous pressure had been a real positive.

Draftees Will Hayward and Oliver Florent have added some speed and excitement to the forward line, while Robbie Fox and fellow debutant Nic Newman have been mostly composed through the midfield and in defence.

"They've been really good and, I think everyone would agree, they've been really exciting," Mills said.

"A few of them have come good in big moments like Will Hayward, and kicked big goals, so they've been really impressive.

"We've been super happy with their attitude and will to help the team."