Time management and strategy were the keys to Carlton's round one NAB Cup according to senior coach Brett Ratten.

However Ratten said he was very disappointed with the start of the first match against Port Adelaide.

"We weren't switched on to play an opposition team we looked like we were coming out for a training run," Ratten said in the post match media conference.

He said the Blues were very poor defensively early on and probably should have been five or six goals down at half time.

"We got going in the second half and our tackle and pressure was much better," he added.

While fans may have been disappointed the Blues let the lead slip in the second game against Adelaide Ratten said it was more strategic than winning the match.

"It was strategic, time management was important, not running out the game. It was a good opportunity for the development of a number of our young players," he said