David Beniuk and Adrian Warren, AAP | March 22, 2009

Wallabies captain Stirling Mortlock has been cleared of a serious leg injury after a sickening collision during the Brumbies' 25-17 Super 14 loss to the Lions in Johannesburg.

Mortlock hobbled off Ellis Park in the second half after his leg was bent back awkwardly, but early indications are he suffered only a cork and could be available for the clash with the Sharks on Saturday (Sunday AEDT).

"At this stage it appears that Stirling has suffered a corked thigh in both legs," Brumbies doctor Warren McDonald said.

"We will monitor him over the next 48 hours and see how he pulls up."

Mortlock walked freely on Sunday and will not require scans, a Brumbies spokesman said.

Coach Andy Friend lamented his side's inability to finish off the South African strugglers, who rebounded from a racism row to post their first victory over the Brumbies since 2003.

"We just didn't finish them off. We had plenty of opportunities, our execution was poor and we didn't capitalise on our opportunities," Friend said.

"We didn't put them under enough pressure."

Asked if there was any reason for that, Friend replied: "No, sometimes you have off nights."

But Friend was satisfied with his side's set-piece work and praised Mark Gerrard's kicking game as the former Test winger continued a strong season in the No.15 jersey.

The Brumbies head to the Indian Ocean city of Durban on Sunday to prepare for the crucial clash with the second-placed Sharks, who will return home with a 3-1 haul from their Australasian tour.

Friend said he didn't expect the travel home to affect the Sharks, just as he wasn't using the 14-hour flight as an excuse for the Brumbies' first-up loss in their three-game trip to the Republic.

"If you let travel be an issue, it becomes an issue," he said.

"You jump on a plane and get home and sleep well and recover from it for a couple of days, you're fine.

"That's not the reason why we didn't win."