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The man who captained Sydney Thunder to their sole KFC BBL title four years ago believes their hero from that campaign, Usman Khawaja, is ready to flip the switch again despite an underwhelming season.

Mike Hussey suggests the axed Test batter is just an innings away from rediscovering his astonishing BBL|05 form in which he posted 109no, 62, 104no and 70 in his only four innings at a strike-rate of 163.5 to lead the Thunder to their maiden trophy.

Now on the outer from the Australian team in all formats having featured in Ashes and 50-over World Cup campaigns only months ago, Khawaja has endured an uncharacteristically lean Big Bash season.

Having averaged nearly 50 for the Thunder leading into his first-ever full BBL season, the 33-year-old will go into Thursday's Eliminator final in Hobart against the Hurricanes without a half-century from his past nine innings.

But Hussey, the Thunder's most decorated ex-player and the club's former director of cricket, suggested those struggles count for nothing going into the knockout clash.

"It's been a bit disappointing for 'Uzzie' but we know how good a player he is and it might only take one piece of luck for him to play a match-winning innings," Hussey told cricket.com.au.

"He might also just come into the finals and just say, 'you know what, I'm going to leave all the baggage behind and I'm just going to go out there and have a crack'.

"When he's in that frame of mind, he's pretty dangerous."

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Khawaja's golden summer of 2015-16 that also yielded four Test centuries is fresh in the mind of Hobart captain and long-time Australian teammate Matthew Wade.

The Hurricanes were giddy during last week's must-win clash against the Thunder at Blundstone Arena when Khawaja, on three, picked out the only leg-side boundary fielder with a sweetly-timed flick that would have otherwise gone for six.

It summed up the second half of Khawaja's tournament, in which a big score has seemed inevitable but not yet materialised.

Wade is hoping it remains elusive.

"You're always fearful when top players haven't piled on the runs," Wade told reporters in Hobart on Wednesday. "Uzzie is a top player.

"I keep thinking back to a few years ago when he played those games at the back-end in the semi-final and final, he hit (two) hundreds. Hopefully he doesn't turn it on again tomorrow night.

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"There's always that fear it's going to happen but the reality is when you've got so many good players in teams, someone is going to perform. We'll just back our skills against theirs."

The fifth-placed Thunder snuck into the finals under the BBL's new system but have their work cut out, needing to win four away games in nine days to lift the trophy.

It's more difficult than their path in BBL|05 under the old 4v1 and 2v3 system, in which Khawaja posted an unbeaten century against the minor premiers Adelaide Strikers and then a match-winning 70 against second-placed Melbourne Stars in the final in back-to-back games on the road.

Hussey stressed Khawaja is a proven big-game player and could easily rediscover that touch.

"It's a crazy thing, that thing called form, it can really just come and go at any time," Hussey said.

"(Khawaja during BBL|05) was just so clear in his mind and he was just in a rich vein of form. He was just literally seeing ball and hitting ball and looking to be very aggressive.

"Sometimes it's just the way it goes in T20 cricket, if you can get off to a really good start and feel good about your game, you can really ride that wave.

"Conversely if you get off to a bit of a rough start and you don't quite feel right you find yourself just chasing the game a little bit, then little things just don't go your way."