Rowing: Drysdale opts out of C/D semi-finals

Mahe Drysdale has withdrawn from the men's single scull C/D semi-finals at the rowing world championships in Chungju, South Korea due to his rib injury. Photo / Getty Images.

Mahe Drysdale has withdrawn from the men's single scull C/D semi-finals at the rowing world championships in Chungju, South Korea due to his rib injury.

Drysdale was set to race this afternoon but found the fractured rib he received in a bike accident last week was further aggravated during the quarter-finals.

He woke up this morning to find muscles surrounding the right side of his chest in spasm.

Drysdale can no longer move his right arm freely; it's the first time he has withdrawn from a regatta.

"I've been trying to manage the injury and was unable to row after the heat, but thankfully had two days to recover. The tough quarter-final yesterday means I'm unable to back up.

Drysdale will stay in Korea for the remainder of the regatta.

He won't train in a boat for about three weeks. It will be up to five weeks before the injury is fully healed.

Meanwhile, lightweight single sculler Louise Ayling has missed a place in the final, finishing fifth in the semis.