Riley Bonner was among Port Adelaide's best in the loss to North. Photo: Brandon Hancock

PORT ADELAIDE coach Matthew Lokan has issued a challenge to his charges after a disappointing 76-point loss to North Adelaide on Saturday afternoon.

Port was in the game and competitive up until quarter-time before the Roosters blew the visiting side out of the water, starting with a six-goal-to-one second term.

Lokan said there were plenty of lesson to take from the game and there may need to be changes in preparation.

“We're not good enough for long enough at the moment, I think that's the lesson for our guys that haven't played a lot of league football,” he told portadelaidefc.com.au after the game at Prospect.

“At this level, you need to be able to perform for longer and unfortunately, we're not able to do it in the moment.

“I challenged the guys after the game to change something they're doing throughout the week, whether that's doing an extra craft session, physically preparing better, getting some more education - we need to do something different to ensure that we can perform better for a longer period of time. “

Port Adelaide has been depleted in recent weeks with injuries at both AFL and SANFL level, but should regain some talent in the next fortnight.

The result against North made it three consecutive losses for Port Adelaide, seeing the club drop out of the SANFL’s top five on percentage and the Roosters take its place.

It has left Lokan to lament his side’s inability to compete for the full four quarters.

“That's probably the story of our last few weeks, that we've been able to do it for patches,” he said.

“The SANFL is a good competition and when you play against good sides, you need to be able to perform for longer.

“At the moment, we're not doing it and we expect better of ourselves.”

The Magpies had three debutants against the Roosters, and Lokan was pleased with their efforts.

“It's been really good for Jake Pasini to play some league football against men, he's been in our system now for 18 months and hasn't really played a game,” he said.

“I thought he was solid and showed he's only going to get better from here and both Bailey [Nicholas] and Tim [Dickson] showed that they're raw and they need some time being able to play league football, but they both performed well and gave everything that they could have.

“Those three guys weren't the reason why we lost the game, I thought they were they were all really competitive.”

The Magpies next take on Central District at Elizabeth on Saturday.