Rafael Nadal will undergo further medical scans in Spain to determine the severity of the knee injury that forced him out of the Australian Open.

The second-ranked Nadal retired while losing a quarterfinal match with Andy Murray due to discomfort in his right knee, the same knee that forced him to spend long periods off the tour with tendonitis, including missing Wimbledon.

Uncle and coach Toni Nadal told Spanish media in Australia that “there is something going on in there, something that wasn’t there before” when asked about the injury.

Nadal is set to undergo MRI scans after arriving to determine the extent of the problem, with Toni Nadal quoted as saying that a preliminary ultrasound showed it “wasn’t a serious problem.”

More In: Tennis | Sport