"It's not the McGraths and Lees but they're still pretty threatening so we have to make sure we're on top of our game and just face up to what we're presented with."
Only four of the Australian squad set to be announced on Saturday will have played more than 25 tests, with five of their probable replacements having played fewer than five times wearing the baggy green.
Opener Watson is viewed as one of Australia's most important players with the bat and the ball, while the withdrawal of paceman Pat Cummins will also be particularly damaging, given the teenager took six wickets in beating South Africa on debut. Their replacements will likely include the recycled and the unproven.
David Warner, who made 65 for Australia A in a warm-up game with New Zealand, will open the batting on his test debut after just 10 first class games, while the bowling attack is likely to be spearheaded by outcasts Ben Hilfenhaus and Peter Siddle.
Hilfenhaus was part of the Australian A attack taken apart by McCullum in his innings of 146, a bowling line-up which the opener rated.
"It was quite a good attack," he said. "We'll find out a bit more about them in the next couple of days but I thought, if anything, they bowled a touch short at the start. Once they pitched it up a little bit, they were a lot more dangerous."
Not dangerous enough to stop McCullum from notching an 85-ball century, nor could it dismiss New Zealand's own young quick Doug Bracewell, who finished the visitors' innings unbeaten on 73 as part of their impressive first innings total of 423.
McCullum picked 21-year-old James Pattinson as the pick of the A attack and said, though he had "no idea" what the opposition test team would look like, whoever was picked would present a challenge to the Black Caps' batsmen.
"The Australian team is still dangerous, it's not the team they had - with five of the greatest players of all time in it - so they've probably come back to the pack a little bit, but they're still very much a dangerous team so we respect that."
The position of the under-fire Ricky Ponting, part of that legendary Australian side, is safe for now, as his experience is only matched by captain Michael Clarke, batsman Mike Hussey and gloveman Brad Haddin.
The Australian selectors could gamble on Pattinson, Mitchell Starc or Ben Cutting from the A side, leaving a novice bowling brigade of Siddle, Trent Copeland, and debutant spinner Nathan Lyon.
