The challenges keep coming for the Swans' backs who, having passed a stern examination from Hawthorn's feared forward line, must now find a way to cut down North Melbourne's tall timber.

The Kangaroos, the Swans' conqueror from last year's finals series, are two games clear at the top of the ladder after their unbeaten start to the season. A victory would further underline the Swans' premiership credentials and give them another major scalp on top of wins against the Hawks and Greater Western Sydney.

North's forward combination of Drew Petrie, Jarrad Waite and Ben Brown will stretch the Swans' back line, particularly if veteran Ted Richards fails to recover from his second concussion in less than a year. Youngster Aliir Aliir is well placed for a recall if Richards is ruled out.

Even without Richards for three quarters, the Swans limited the Hawks to only seven goals from 54 entries inside 50, a staggering improvement from the previous week.

The increased pressure up the field made the job easier for the Swans' defence but they were also given a lift by Grundy, who rebounded from a poor game against Richmond with one of his best for the season.

The 29-year-old was close to impenetrable in the defensive 50, his ability to read the ball in the air quelling Hawthorn's forward thrusts while also launching several counterattacks for his side. It was an emphatic response from Grundy, who came under fire from critics such as former premiership players Matthew Lloyd and David King last week.

Lloyd had described Grundy, along with Richards, as one of the club's "biggest concerns", while King said he had become vulnerable.

"They can say whatever they like, they've said it for a number of years," Grundy said. "We don't rely on just the back six, we're an 18-man offence and defence. We rely on the whole team and not just four or five of us down there. If one guy down in the forward is not doing his part it hurts the guy in the back line."

The acid test for the Swans' defence will be how they respond when their on-ball brigade is being beaten, and they are isolated in one-on-one contests.

"My one-on-ones is one of my strengths," Grundy said. "It's something you have to be able to do. I didn't do it last week which was disappointing. I've got to bring it each week, it's always a challenge and we'll be tested next week against their forwards."

Grundy said he was stung by his game against the Tigers: "I was pretty disappointed with my game. I set myself a pretty high standard and didn't deliver. We wanted to turn that around, we've been pretty good all year and last week was a real letdown. We thought we played some pretty good footy [against Hawthorn], under pressure we were pretty composed."

Swans coach John Longmire praised Grundy's effort to guide a young defence once Richards was out, a point echoed by Josh Kennedy.

"We rate him really highly, I still think he's a quality defender," Kennedy said on Channel Seven's AFL Game Day. "Our defence, as a unit, to respond the way they did is really promising. A lot of those players are leaders at our football club and we need them to stand up and they did, they responded well."