By the time he'd played the eighth of his 117-Tests, Ashley-Cooper had already started at fullback, both centre positions and on the wing.

Back playing Super Rugby in Australia for the first time since 2015, the 35-year-old has enjoyed the rare luxury of playing in just one role this year.

While rotations have caused numerous changes in the Tahs backline, all six of Ashley-Cooper's starts have been at outside centre.

"It is a blessing being able to put in performances back-to-back in the same position," Ashley-Cooper said.

"You're able to grow and develop your game in that one position and really focus on the improvement areas and your strengths.

"Towards the end of my career I've really enjoyed 13 because it's probably where I feel most valuable."

Ashley-Cooper returned from overseas to rejoin the Waratahs this season, with a goal of playing at a fourth World Cup.

"I'm focusing on the role here because I know if I perform well here that (World Cup selection) will take care of itself," he said.

Ashley-Cooper aims to make more progress when the Waratahs hope to back-up their win over Australian conference leaders Melbourne when they play the Sharks in their first game at western Sydney's new Bankwest Stadium on Saturday.

"For us its about stopping their momentum, they are a gain line focused team," Ashley-Cooper said.

"They are a team full of big athletes, big bodies and a lot of attacking threats particularly in that back three, so defensively we've got a huge job."

Only once this season have the Tahs won back-to-back with their inconsistency underlined by losing at home to the Sunwolves a week after toppling the competition benchmark Crusaders.

"This week has been about us wanting to go out there and put in a performance off the back of a good performance," Ashley-Cooper said.

"We're looking to build that consistency because we're at a pretty important time in the season."

Australian Associated Press