Ed Hawkins looks at the strengths, weaknesses and Australia ins and outs of the four teams remaining in the hunt for glory...
"The Strikers have been victims of their own success. Gone are their captain, Travis Head, their top scorer, Alex Carey and the 11-wicket Billy Stanlake"
The Scorchers have won three of the last four Bash titles. And they have the best win ratio in the world. So it's not in the least bit surprising that they are the favourites. If they win their home semi, it's a home final by dint of topping the group.
But is it really a home game? In terms of a packed and partisan crowd, yes. The Optus Stadium will be rocking. But they don't know the wicket like they did the Waca, where they were almost unbeatable.
Perth could pine for the old ground because they look likely to hit their semi-final opponents, Hobart Hurricanes, with all-out pace. Ashton Agar's call to Australia's T20 squad means he misses out.
So Mitchell Johnson, Jyhe Richardson, Tim Bresnan and Matthew Kelly could team up. It's a big risk considering the importance of spin in England's win at the Optus on Sunday. James Muirhead, an inexperienced grade player, could be called in to offer wrist spin.
If Australia take away with one hand, with the other they give back, however. Mitchell Marsh, the powerful all-rounder, should return to the squad. He could also be joined by his brother Shaun Marsh, which would strengthen a Perth batting line-up which has had the odd wobble.
Could their nickname prove prescient? Unexpectedly, they blew up a storm - winning five-in-a-row - and just as quickly the chaos disappeared. It's not three straight losses for the Hurricanes. Talk about losing momentum at the worst time.
And anyone who saw their defeat by that ragged crew Melbourne Stars in their final match might have lost faith in their ability to rediscover it. It was a shocker of a performance. As usual, their excellent batting fired and at the break it looked job done.
Previous to this season, it was their bowling which had consistently let them down. Jofra Archer looked to have solved that on his own. But old problems returned to haunt them and Stars got up from 71 for four in the tenth to complete a surprise, and eventually easy, win.
Tymal Mills was the chief culprit, although there seemed to be an alarming lack of composure all round when the pressure came. Mill went for 14 an over. It's impossible to sympathise for him or the 'Canes because he's been exorbitant all season.
The problem Hurricanes have is that Mills probably has to be picked. D'Arcy Short, whose wristspin gave them the option of leaving Mills out and adding to their batting power instead with Nathan Reardon, will not play because he is with Australia. That robs them of the top runscorer in the tournament but also flexibility to change-up the line-up. It's tricky to see where Hobart have an edge against Perth therefore.
The Strikers have been victims of their own success. On the brink of their first final after a terrific league campaign which garnered seven wins and only three losses - two to the venerable Scorchers - Cricket Australia reigned down three mighty blows on them.
Gone are their captain, Travis Head, their top scorer, Alex Carey and the 11-wicket Billy Stanlake. The trio have been asked to stem England's one-day dominance in the T20 series.
Head and Carey leaving weaken significantly a batting line-up which has not been entirely convincing. When they have come up against the measured Perth attack for example, they have faltered horribly. The 670 run-sized hole left by Head and Carey cannot be filled, even if we admire Colin Ingram.
So there will be plenty of pressure on Rashid Khan and Peter Siddle, who have been epic with the ball. Against Melbourne Renegades in the semi-final, the pair must surely need to repeat their series economy rates of 5.5 and 5.8 respectively to give their batters a chance.
On first inspection, the match odds for this clash seem generous on Strikers at [2.08] but the player drain they have suffered may mean they are not quite big enough.
We suspect that the Renegades are a very average team. They don't really seem to excel at anything. Their batting, shorn of Aaron Finch, is so-so while their bowlers plod in and plod on for about eight an over. No disgrace in that, of course, but where is the x-factor?.
Mohammad Nabi, their most economical bowler at 5.7, is with Afghanistan that's where. Kane Richardson, their third best in his absence at a rate of 8.05, has been called up for Australia. Pressure then on Tom Cooper and Chris Tremain.
Their West Indies pair, Dwayne Bravo and Kieron Pollard, are supposed to be pulling their weight with bat and ball to bridge the gap to the top sides. But only Bravo is managing it with the ball. He has 17 wickets. Pollard is going for ten an over. Between them they've contributed 112 runs.
At least Cameron White, the skipper, is back from Australia duty to bolster a batting line-up which can look a little unsure of itself when Aaron Finch is not there (which he isn't).
White's return and the form of Cooper and Marcus Harris might mean Renegades are the closest thing to value in the semis at [1.91] on the 'to qualify' market. And perhaps their metronomic, or rather dull appearance, in the field is unfair considering there are only so many Afghan spin wizards around.