Brisbane coach Chris Fagan demanded a swift response from his vaunted midfield unit after rampant Port Adelaide ran roughshod over the lacklustre Lions in a surprise 54-point rout at Adelaide Oval.

Fagan’s men were on the back foot early on Saturday but looked to have the game where they wanted it, leading by three goals late in the second quarter.

But Lachie Neale, Josh Dunkley and company were no match for Port’s young on-ballers in the second half.

The stats sheet made for grim reading for Fagan, with the Power gathering a whopping 141 more possessions, taking 59 more marks and going inside 50 25 more times.

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Asked what his midfielders needed to take from the shock performance, Fagan was direct.

“They need to just respond,” the coach said.

“Sometimes you get beaten in sport, you don’t win every week, in our practice games against good midfields we’ve had good results, but we got cleaned up.

“Interestingly enough, we had our hands on the ball first a lot of times and just coughed it up.

“Their pressure was great and we were off and we haven’t got long to work out how we get better.

“All our boys who played, bar two, have had plenty of match practice in the last six or seven weeks so we’ve got no excuses and we’re not going to make any.”

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The Lions face Melbourne in a marquee match-up at the Gabba on Friday night.

Fagan saw no hint of the alarming display during a strong pre-season that included good performances against Sydney and Geelong.

“We came into the game with confidence given our (pre-season) form but perhaps that was the problem,” he mused.

“For some reason or another the effort wasn’t there, our reaction time was poor and all the things that we pride ourselves on were not evident.

“We had two good games against the Swans and Geelong … whether that was an influencing factor, whether we turned up here and perhaps thought we were going a little bit better than we were?

“It’s hard to say.

“It was a very disappointing performance and not one that’s typical of our club in the last four years.”

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Keidean Coleman will be monitored after he left the ground and was unable to return following a head clash and is likely to be sidelined for Round 2.

The Lions are a chance to regain former skipper Dayne Zorko when they look to bounce back against the Demons.

“He may be some chance this week … he was pretty close,” Fagan said.

“He played about 20 minutes of match sim on Tuesday and played pretty well.”