McCullum was unable to take part in the pink ball trials held in Hamilton as he was in London to stand as a witness in the perjury case of Chris Cairns.
Speaking about the opportunity given to Southee, New Zealand coach Mike Hesson said that the 26-year-old is looking forward for the challenge.
“It will be a good opportunity for him (Tim Southee).
“Part of his role in the leadership group is to take a little bit more responsibility.
"I think he's looking forward to it."
It has been almost five months since McCullum last played a Test match, but Hesson is confident that the 34-year-old will be ready come the first Test.
"He'll play a part, but Brendon has been away from training for a little while.
"He's looking forward to getting back into that.
“We'll ease him back in, make sure he's ready to go by Brisbane.
“We've known the timelines for a long time, so we've put plans in place and Brendon will be ready by Brisbane.
“He's very much on track.”
New Zealand, who are touring Australia for the first time since 2011, have last beaten their trans-Tasman rivals in an away Test series in 1985.
Since 1985, New Zealand have played 22 away Test matches against Australia and have managed to win only three times, while suffering 11 losses.
Hesson knows that Australia hold a formidable home record and acknowledges that New Zealand will have to play their best cricket if they have to win the series this time around.
"There's been some good New Zealand sides come over here in the past and I think it's shown how formidable Australia are in their own backyard.
"1985 is a long time ago.
“A lot of us still remember that quite fondly.
“We've had the odd Test win, in 2011, but to win a series over here you know you have to play very well.
“We won't get too far ahead of ourselves."
Australia were exposed against quality fast bowling in the 2015 Ashes which they lost 2-3, while suffering some spectacular batting collapses in the third and the fourth Tests of that campaign.
The New Zealand coach is confident that if Southee and Trent Boult can hit the right strides, the Blackcaps can put pressure on Australia.
"Anyone in the world struggles against the swinging ball.
"That's shown over the last few years, and Tim and Trent are pretty good exponents.
“I think if those two get it right and it does swing, they can put any side under pressure.
“Australia is no exception to that."
For the hosts, Mitchell Starc will be their pace spearhead after picking up 33 wickets from eight games in 2015 at an average of 25.78.
In the ongoing Matador BBQs One-Day Cup, Starc has an impressive haul of 23 wickets from five games at 7.47 runs per wicket.
Hesson opined that the key to facing Starc was to carefully see out the early period in the match where there is help for generating swing.
"He's a high quality bowler, especially in white ball.
“In Test cricket he's obviously very good as well, but probably doesn't have quite the record that he has got with the white ball.
“The key thing with any bowler is to take them a bit deeper, and if the ball stops swinging it's a little bit easier.
“Plenty of hard work to go into that beforehand."
This year’s New Zealand tour of Australia will be known for being the first series to host a day-night Test match which will be played with the pink ball.
Excited about the day-night Test, Hesson felt that the training camp in Hamilton helped the players get used to the unknown.
"That (training camp in Hamilton) removed an element of the unknown.
"I think the guys enjoyed that.
“A one-day game with white clothing and pink ball will be a little bit of a novelty in itself, a nice way to start the tour."
The New Zealand tour of Australia will get underway with the first Test which will be played in Brisbane between 5th and 9th November.
© Cricket World 2015