The hosts finished day one in Adelaide on 273-5, having been 155-1 at one stage.
"It has been an interesting one," he told Sky Sports News. "At 155-1 we were thinking 400, 500 was on the cards but then a few tricks started happening and they got a few wickets so we then thought maybe 300.
"We have got a good tail, though, so hopefully we can push on and I think 400 would be a good score."
Australia won the first Ashes Test in Brisbane last month.