St Kilda star Jake Carlisle was forced to pass a fitness test moments before the start of the side's clash with North Melbourne.
Carlisle pulled up sore in the warm-up with trainers by his side, with concern around his lower back.
Triple M boundary rider Michael Roberts said there was plenty of concern when Carlisle did limp down to the rooms.
"Jake Carlisle, lower back, limped off," he reported.
"He did it in the warm-up. There's real trouble here."
He later said Carlisle seemed to pass the test.
"There was a problem with his lower back," he said.
"He was able to kick both left and right feet, he was able to kick it long, as Duck said.
"He's joined the huddle in the rooms."