Lions coach Chris Fagan has been forced to make one change to his winning line-up with ruckman Stef Martin ruled out with a back injury.

Archie Smith replaces Martin in the squad to take on Melbourne at Metricon Stadium on Sunday alongside Keidean Coleman, Alex Witherden, Rhys Mathieson and Connor Ballenden who have been named on an extended bench.

Smith returns after playing in wins over West Coast and Adelaide earlier in the season.

Martin had been restricted in his capacity to train while the side was in their hub in Manly, NSW and had also been playing through pain for several weeks.

Upon the club’s return to Brisbane he was taken for scans which revealed the extent of his injury.

Lions GM of Football David Noble praised the star ruckman for his ability to get up for recent games but said it was now clear he faced an extended period on the sidelines.

‘After a couple of weeks persevering with some referred pain, recent scans have revealed that Stef has a stress fracture in his lower back,’’ he said.

“Further investigation and scans will be done in the coming days to fully diagnose Stef’s injury.

“Unfortunately, this will rule Stef out for up to 8 weeks until we get some certainty around the injury.

“Stef has shown enormous resilience over the last few weeks as well as the last several years.”

The extended 26 man squad will be trimmed on Friday.