Adam Ashley-Cooper knows time is running out and is desperate to cash in on the NSW Waratahs' star-studded roster and finally snare a Super Rugby championship in 2014.

The veteran backline ace turned 30 this year, but the most meaningful pieces of silverware on offer - World Cup, Bledisloe Cup and a Super Rugby trophy - still elude him.

With the Waratahs slipping out of the top six for the first time this season after last weekend's bye, Ashley-Cooper admits to getting more and more anxious.

The eighth-placed Waratahs will walk the finals tightrope if they lose to the Lions at Allianz Stadium on Sunday.

"I've become more and more desperate, absolutely. Not being able to contend for a Super 15 trophy," he said.

"I know my days and years are limited here and my opportunities are, so this year is certainly the only year I'll probably have a really good chance of winning a Super title.

"That's off the back of where we are at the moment and the squad that we have. So keeping that in mind is more than enough motivation week in, week out."

The Wallabies star says his sentiments are shared by fellow senior members of the squad and that's why the Waratahs aren't taking the 11th-placed Lions lightly, despite beating the South Africans 10 times in a row.

"The competition this year is that anyone can win on the night; just thinking about that certainly will allow us to prepare for this game a little bit better than we would have in previous years."

Tahs lock Jacques Potgieter confirmed his place on the bench on Friday after he proved to coach Michael Cheika he'd fully recovered from a leg injury. AAP