Back-to-back wins over the Thunder and Melbourne Stars have the Sixers poised to deliver a telling blow to the Brisbane Heat's finals chances tonight, which would be another boost to the glamour franchise's pride, which took an almighty hit when it lost six matches to start the season.

Hard hitting left-hander Nic Maddinson is adamant there is still much to play for and has vowed to maintain his carefree approach, which allowed him to plunder 62 runs in Tuesday night's eight-wicket thumping of the Melbourne Stars.

It was his and the Sixers' best performance of the season and emphasised just what might have been for the men in magenta had they taken their chances earlier in the summer.

"We could've easily been two wins out of our first three or four games and it could've been a completely different season," Maddinson said.

"We've been playing fearless cricket the last couple. At times in big moments of the games we were second-guessing ourselves in some early games, but now we're looking to take the game on.

"It's about playing good cricket regardless of whether you've had a run of losses or not. People are still playing for their career in the end and trying to further their career and further their chances of playing at a higher level.

"[There is] still a lot to play for; we have a great fan base here in Sydney. Two home games to go, we'd like to finish off with two wins for them and hopefully ahead of the Thunder, too."

Maddinson said morale at the Sixers had remained high all season despite the 0-6 start.

"Our two overseas guys [Jason Roy and Sam Billings] that we had early in the tournament drove that a lot as well - they're full of energy and pretty good guys around the squad, even when they weren't performing," Maddinson said.

"We always felt like we weren't far away from winning. There's been no negative energy coming to training, it's all positive.

"You've got to let the game go pretty quickly once you've had a loss in T20 because as we find you're playing a day or two later again and need to perform."

Sydney's turnaround has coincided with the return of Test off-spinner Nathan Lyon who was instrumental in the win over the Stars, taking three key wickets from his four overs. Lyon has enjoyed two wins from two starts with the Sixers this summer since fronting up after Ashes duties.

"When I came into the squad for the first time last Friday, the morale in the team is actually quite impressive, the boys are training hard, we're preparing the best way we can prepare," Lyon said.

"When you're none from six you can start in-fighting and all of that stuff but there's been none of that. We know moving forward we've got a lot to play for.

"We need to go out there and pay them [the Sixers members] respect for the faith they've been showing in us. I'm really hoping it's a packed house come Thursday night and the following Tuesday for our last remaining game.

"It's just about going out, enjoying playing cricket for the Sydney Sixers and for all the young fans out there as well."