Gold Coast’s defence looks set to again be tested in their last AFL practice match against Collingwood on Sunday after Rory Thompson was all but ruled out.

News that a gastro bug had struck down key defender Rory Thompson would usually leave Gold Coast Suns coach Guy McKenna feeling sick in the stomach.

Especially after Thompson missed the club’s first two AFL pre-season games recovering from hip surgery.

And with prized defender Nathan Bock still not in sight of a return from a severely broken leg.

However, McKenna backed the Suns’ defensive depth after all but confirming Thompson would be sidelined for their final practice match against Collingwood on Sunday.

McKenna is set to welcome back big guns Gary Ablett, Jaeger O’Meara, David Swallow and Michael Rischitelli against the Pies after resting them from their 47-point loss to Brisbane Lions in Townsville last weekend.

However, the Suns mentor baulked at easing in Thompson after the big redhead fell ill on the weekend.

While McKenna did not rule Thompson out of their AFL season opener against Richmond on March 15, the Suns coach said their defensive depth ensured the youngster would not be rushed back.

“Do you roll him out when he is not quite feeling right and the answer right now would be no,” he said of Thompson.

“It puts him at risk for round one but I would prefer him to be right for the other 21 games.”

McKenna still could not give a return date for Bock but believed it was a matter of time after the former All-Australian had a steel rod removed from his recovering leg.

Bock has only played six games in the past two seasons after suffering a severe broken leg against Fremantle in round six 2012.

“The rod is out. Now he is going into uncharted territory, getting used to the stress in his leg,” McKenna said.

“We understand it is going to take time but we have to get it right for a player of his quality and class.”

Still McKenna was not searching for the panic button after the likes of Steven May and Matt Warnock had blossomed in defence in Bock’s absence.

“Of course we would like Rory and Nathan back but we can cover it,” he said.

“Steven May has grown and Matty Warnock has certainly shown something.”

The jury is also out on midfielder Dion Prestia and Trent McKenzie (both calf) ahead of the Pies clash.