Fremantle have been dealt a further blow with news captain Nat Fyfe’s hamstring injury is significant and is likely to sideline him for up to five weeks.

Veteran ruckman Aaron Sandilands will miss the next three weeks with a calf injury sustained in the warm-up to Sunday’s loss to Brisbane.

It means the Dockers will be without their two most important players against Melbourne, Port Adelaide and Essendon with Fyfe also likely to miss the round 19 clash with Hawthorn.

Dockers football manager Chris Bond said Sandilands’ calf injury was minor and they hoped Fyfe could return sooner.

“We know how professional Nat and Aaron are,” Bond said.

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“We see Nat’s injury being a four to five week injury. Hopefully, it may be sooner, it just depends on how he pulls up.”

Meanwhile, Fremantle chief executive Steve Rosich said it was inevitable the club would review preparation over the bye before the Brisbane game but dismissed the notion that a mid-week rules trial with the AFL was a factor in the performance.

The Dockers lost Sandilands and Fyfe and were out-run and out-worked by Brisbane from siren to siren. Rosich said almost every performance, good or bad, was reviewed by the club and Sunday most certainly would be.

Camera Icon Nat Fyfe had an ice pack put on his hamstring during the game. Credit: Getty Images

“Our mantra on almost everything is plan, do and review. It is possible that the program contributed either physically or mentally to the game on the weekend,” Rosich said. “It would be negligent if we don’t have a look at it so we will for sure.”

The Dockers did two short quarters of match simulation on Wednesday morning to try proposed new rules to beat congestion the AFL is considering for next season.

Rosich said it would be up to coach Ross Lyon, strength and conditioning coach Jason Weber and Bond if that was included in the review but he doubted it had an impact.

“It provided a match element to training which would have been part of training anyway. It is unlikely that would have been a factor at all,” he said.

“The reality is that it is a young group, lots of fresh faces and a lot of them would have been dealing with having a bye in an AFL system for the first time.”

Rosich said the Dockers supported the bye but it meant teams went into games off vastly different breaks.

The Dockers hadn’t played for 15 days when they took the field on Sunday.