So it's no surprise he's bursting with pride the Green Machine have rediscovered the tough mindset which helped propel them to the 2016 preliminary finals.

A traditionally strong attacking team, South Sydney scored more points than Canberra last year, but finished with the fifth-worst defensive record to miss finals for a second straight year.

But a 5-1 start to the season has been built on a defensive wall which has leaked a league-best 11 points per game.

The Raiders play Manly in Sydney this week before they host Penrith in Wagga Wagga next Saturday afternoon, the second NRL game held in the city.

"I think it's more their mentality more than anything else, there's a real hunger about them," Tongue said.

"Against Parramatta (19-0 win in round five) there was try-saving tackles right at the end, there's some real pride in that which is standing out for me.

"It's come to the surface and they're playing for each other, which is the main ingredient for rugby league.

"We try and complicate it so much but if you want to rip in and work hard for each other, that's the biggest battle to get over.

"You could probably argue with their huge defensive focus, maybe their attack isn't 100 per cent firing at the moment, but when you bring a new five eighth (Jack Wighton) and fullback (Charnze Nicoll-Klokstad) it'll take time, but you can see it starting to click."

Over 5000 tickets have already been sold for the clash with the Panthers at Equex Centre next Saturday, which already eclipses the 4115 attendance for the Roosters-Gold Coast clash at the now defunct Eric Weissel Oval in 1998.

Despite registering their best start to a season since 2003, Tongue warned the Raiders have yet to reach their full potential as they integrate a new 'spine'.

"They're getting a lot of raps and they deserve that, but I think there's a hell of a lot of improvement in them," Tongue said.

"They would argue too they're not at the stage of the Roosters and Melbourne at this point in time, but there's a lot to like about it."

Tongue said Wighton's move from fullback into the defensive line had started a domino effect which has made the Raiders a tough nut to crack.

"Bringing Jack into the front line as a really strong defender, Crokes (centre Jarrod Croker) has seemed to get a lot of confidence out of it too," Tongue said.

"It's helped that left side which had leaked a few points here or there, but he's one of those guys who builds confidence in people around him and that's what I've seen on that whole left edge."

The Raiders are booked in to play another game in Wagga next year, but Tongue believes there's a big opportunity to forge a long-term presence in the Riverina, similar to Penrith's association with Bathurst.

"The opportunity to go back for a number of years, you can really start to grow an imprint," Tongue said.

"I think Wagga would really appreciate that, they've got great facilities and it's close to Canberra as well."

READ MORE