Clarke had been an outside chance to fly to Wollongong if the Perth Test finished early, but after the loss to South Africa, now remains in doubt for Saturday's Big Bash League opener against the world champion Sixers.

Instead, Clarke is likely to focus on the upcoming three-Test series with Sri Lanka starting in nine days' time in Hobart, following the emotional farewell of former Australian captain Ricky Ponting.

Khawaja was to play for the Thunder tonight before he was selected to captain the Chairman's XI in Sri Lanka's three-day tour match at Canberra's Manuka Oval.

However, the Thunder still boast high-profile players including stand-in skipper Dirk Nannes, New Zealand batsman Martin Guptill and one-time Test batsman Chris Rogers.

The Wollongong line-up features several NSW players, including Adam Coyte and David Dawson, and will be captained by former Australian opener Phil Jaques.

Dapto batsman Michael Stephenson, who has played the last four years in the Illawarra representative team, will be lining up.

"With the international players involved, it's by far the biggest game I've played in," Stephenson said. "It will be good to see what they do differently than what we do."

Stephenson admits Nannes, capable of sending down 150km/h thunderbolts, will be a handful.

"I'm looking forward to that, it will be a challenge," he said.

"As soon as the lights come on and the dew comes in off the beach, the ball goes through on the dewy deck. Hopefully we can bat first and then get the chance for us to bowl at night.

"It's their only hit-out after coming together [in Sydney] on Monday, so it's going to be a big challenge for them as well.

"I've been happy with my form, I've had a couple of scores, just haven't gone on with a big score."