Simpson said it was difficult to be critical of the Roos, as he believes the contest could have gone either way.
"We were both out on our feet and they played for an extra 20 minutes last week, so we thought we'd have the legs. But they stood up right to the end," the former skipper told kangaroos.com.au.
"It was just one of those games … in the end they got over the line.
"Dean [Laidley] spoke about that (tenacity) after the game. When you lose like that, you can't point to any real incidents. They've (Western Bulldogs) got some bigger bodies and a bit more maturity and they've got some young kids who are playing some great footy.
Although he was arguably North Melbourne's best against the Dogs, Simpson, who claimed 26 disposals (10 contested) and seven inside-50s, was blaming part of the loss on himself.
"I'm just thinking about the last centre bounce. I've thrown it on the boot … but I've got caught up in the razzamatazz and got caught holding the ball and they went down and kicked a goal," he said.
"So I can't get that out of my mind at the moment and I feel responsible."
Nevertheless, Simpson’s four-quarter effort was outstanding, something he believes may be down to an easing of responsibility.
"I suppose, now that I'm [playing] more of an individual role with 'Boomer' [Brent Harvey] taking over as captain, I can concentrate on getting myself right."
And Simpson's contribution was not lost on coach Dean Laidley.
"If Adam could play in these conditions every week, he'd play until he was 40 years of age – he's super," he said.
"That's probably the first time for a few weeks we've actually put him in the middle – he's been more wing, forward, but I thought his attack on the ball was outstanding."
Meanwhile, Simpson believes the signs are promising for the Roos for the rest of 2009.
"We've always thought we can be competitive against the top teams and we hadn't been beaten by the Doggies since 2005. We've got the Hawks next week and we beat them the last time we played them, so I think we're going to be competitive," he said.
