PORT Adelaide forward Robbie Gray has been withdrawn from the side to play Melbourne at TIO Stadium on Saturday night due to back tightness.

Days after signing a new two-year deal with the Power, Gray was a notable absentee when the team arrived in Darwin on Friday afternoon.

"He had back tightness from last week and we made the call on him this morning," football manager Peter Rohde said.

"With back tightness it is a bit hard to fly up here today, play tomorrow and fly back the day after, so we made the conservative call to rest him. But we are very confident he'll be right for next week.

"Certainly if we had been playing at home, he would have had another day to prove he was fit so it would have been a lot easier. But he had a bit of stiffness last week as well and he was starting to get into the cycle where he hasn't been able to train much.

"He'll be able to have a full week of training now and go into next week's game feeling good."

Coach Mark Williams put his side through a brief 30-minute training session in muggy conditions on Friday afternoon.

As a result of a thunderstorm which rolled through the city earlier in the day, several players experimented with gloves and sweatbands.

Playing games in the heat of the Top End has provided teams with tricky conditioning issues in the past.

However, with the mercury hovering around a comfortable 25 degrees late on Friday with similar temperatures expected on Saturday evening, Rohde said the heat wasn't a major factor.

"In the past we've done heat chamber work when we've come up here in the middle of our winter, but it's been fairly warm in Adelaide," he said.

"We've had mid-20s pretty much all the way through so it's not such a big change this time of year. We're obviously very keen on rehydrating and preparing well from that point of view.

"It's nice to get out here and get a bit of feel for the ground, but we come up here a fair bit now so we're quite used to the conditions."

Former Bomber Jay Nash and veteran Josh Carr travelled with the team as emergencies with Rohde backing Nash to make his debut for his new club.

"We're certainly leaning towards Jay, but we'll see what the weather's like tomorrow and balance that up closer to the game. We would expect that Jay would play his first game for us," he said.

"Obviously he's a player we brought across and he hasn't had the opportunities early in the season he might have liked.

"He had a bit of a hamstring injury in the pre-season and missed a bit of time, so he has taken a bit of time to get his form up in the SANFL, but his last month has been really good so he deserves his chance."