Guts key to spin bowling - Ashwin
A legspinner tossing the ball high, giving it a rip with his wrist to lure the batsman out before getting it to dip, grip, turn and earning a stumping. An offspinner tossing the ball high, giving it a tweak with his fingers to draw the batsman forward, getting it to drift, grip, turn and earning an outside edge to slip. These are not dismissals you normally associate with Twenty20 cricket. But these are just two instances of what Amit Mishra and R Ashwin have been able to achieve in this World T20.
Both spinners have had principal roles to play in each of India's four successive victories in the group stage. On three of those occasions, they have not had the weight of runs backing them, as India relied on their preferred strategy of chasing. All three of those matches - against Pakistan, West Indies and Bangladesh - were 'live' ones, with qualification for the knockouts dependent on their results. Mishra was the Man of the Match against Pakistan and West Indies; Ashwin got the award against Bangladesh.
Two subcontinent sides supposedly accustomed to playing spin, and a third which has backed itself to hit the big shots under pressure, and have done so in crunch matches against Pakistan and Australia. None of them managed even 140 against the Indians.
The conditions have been spinner-friendly in Bangladesh, particularly so in Dhaka. MS Dhoni has said it has been one of the main reasons why the Indian slow bowlers have done so well. Ravindra Jadeja hasn't been among them, though. It is not really his style to lure batsmen with flight and guile.
But no matter how much the conditions support you, it takes tremendous heart for a spinner to bowl slow when the temptation is to fire it in quick. To overcome the ever-present fear of getting hit in T20 and toss the ball up. For one spinner to do it in a single T20 is itself remarkable. For two in the same XI to do it over the course of a world tournament with so much control is incredible. Ashwin, and particularly Mishra's, biggest achievement this World T20 has been to consistently beat this fear, and do so without the security of a big total to defend every time it mattered.
This absence of fear, or presence of "guts", over four matches is what South Africa will be up against. It was a term Ashwin used several times ahead of India's semi-final clash. "In terms of variation of pace, you need a lot of guts," Ashwin said. "If you're at the top of your game, you can land the ball exactly where you want it to land.
But apart from that, to actually slow the ball down when the batsman's going after you is a key component of this particular game, for which you need quite a lot of guts. And if you've gone for a six, it requires even more guts to come back the next ball. Those are the key components of a winning game, as far as I'm concerned."
It tells you a lot about a spinner's state of mind when he says the ball is behaving as he wills it. "In the last two or three months, I feel that I'm probably at the top of my bowling game," Ashwin said. "When I reach that phase, I pretty much don't practice at all. That's a phase I'm in right now. The ball is landing exactly where I want."
South Africa will have to counter Mishra and Ashwin on a helpful and unfamiliar surface - they have been playing in Chittagong so far - and that too in a knockout. Bowlers have not had to contend with heavy dew turning the ball into soap in Dhaka, like it did so often in Chittagong.
South Africa have probably the most nerveless innovator among current limited-overs batsmen in AB de Villiers, and they will need to keep calm when it comes to taking on spin. South Africa also have the Super 10 stage's leading wicket-taker in Imran Tahir, who's managed 11 wickets in less helpful conditions with his mix of quick sliders and googlies.
He's had a well-publicised visit from Shane Warne in the Mirpur nets. Will he stick to what has worked for him in Chittagong, or will he use more flight and turn like the Indians have? Whatever method he uses, Ashwin said it would again come down to the same word - guts.
"When it comes to international cricket, there's a very small margin between the quality of spinners. Everybody's bound to have a certain amount of quality in them. It's all about the mental make-up of the spinner and the amount of guts he has in that particular scenario," Ashwin said. "It'll be handling pressure that makes the difference, because Imran Tahir has been in top form. And I expect (Aaron) Phangiso to play. When that happens, you're pretty much evened out on the amount of spinners both teams will play. It comes down to how well your spinners handle it."
Apart from pressure, the spinners might also have to deal with a wet outfield, as rain is expected around the time of the match on Friday. The last time rain came down in an India game in a World T20, against Australia in 2012 in Colombo, it contributed to their exit from the tournament, as their three spinners found it difficult to grip the ball. Even Mishra and Ashwin, for all their heart, could struggle if it rains again.
Abhishek Purohit is a sub-editor at ESPNcricinfo