BRISBANE has ruled former skipper Dayne Zorko out of Saturday's opening round clash against Port Adelaide as he continues to battle a hamstring injury.

Zorko suffered the setback last month and has been slow to progress, but did complete a strong session on Tuesday morning.

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However, the Lions have decided to be cautious with their 34-year-old veteran, opting to put a line through his name for round one.

"Dayne is training really well and has made significant progress, but we need to ensure he has the opportunity to get more training volume under his belt," said Lions high performance manager Damien Austin.

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"The priority is to have him not only 100 per cent ready to play but 100 per cent ready to continue to play once his season gets underway."

Meanwhile, reliable defender Darcy Gardiner has still not overcome an ankle injury and will also miss the clash with the Power.

Gardiner had off-season shoulder surgery, but on return from that picked up the ankle problem that has seen him sidelined for weeks already.

He did some light running to the side of Brisbane's session on Tuesday, as did Callum Ah Chee (quad) who is also still a week or two from returning.