The pace-spin equation, and a D/L snippet

In the lead-up to the ICC World Twenty20, what was generally agreed upon was that the pitches in the West Indies would greatly assist spin, and that spinners would be far more difficult to get away than fast bowlers. Intuitively that seems a reasonable assessment, as the pitches have lost much of their pace at most venues there. Add to that the fairly large outfields, which generally help spinners get batsmen out caught in the deep, and it's fair to assume that spinners will enjoy the conditions more than the fast men.

What's transpired so far - till the end of the group stage - though, is quite different. Spinners haven't done badly, taking 50 wickets at a decent average and economy rate, but they've been upstaged by the fast bowlers. In the first 12 matches in the World Twenty20, medium pace or pace has taken 90 out of the 140 wickets that have fallen to bowlers, at an average of 17. The three leading wicket-takers - Dirk Nannes, Mohammad Aamer and Darren Sammy - are all from that category, with all of them averaging fewer than 10 runs per wicket. Hamid Hassan of Afghanistan and Shaun Tait have sub-ten averages as well.

On the other hand, while some spinners like Daniel Vettori and Shakib Al Hasan have done well, several others have had less success than anticipated. Yusuf Pathan and Mohammad Hafeez are among those with economy rates of more than 10 runs per over. And the ploy of opening the bowling with spin hasn't met with much success either: on the 11 occasions when they've bowled the first or second over of an innings, spinners have gone for 70 runs without taking a single wicket.

The performances of pace and spin so far in the World Cup are a departure from their overall records in Twenty20 internationals. In all matches, pace- or medium-pace bowlers average 23.76 runs per wicket and concede 7.53 runs per over; the corresponding numbers for spinners are 20.77 and 6.76. Doing the same analysis for matches featuring only the top 10 teams (excluding the Associate countries), the difference is still similar: fast bowlers concede more runs per wicket and per over compared to spinners.

One of the reasons for this could be the period of the innings when these bowlers are used: fast bowlers have usually bowled the first few and the last few overs of 20-over games, when batsmen are more inclined to take chances. However, the good performances of spinners in a format in which it was initially feared they'd have no role has encouraged captains to use them more often in difficult periods. That trend was noticeable during the IPL, and it's likely to continue in internationals as well.

So who are the best fast bowlers and spinners in this variety? The next two tables list the top ones, sorting by economy rates those who've bowled at least 40 overs (only matches involving the top 10 teams). Among the fast bowlers, six have an economy rate of less than seven, with the injured Umar Gul being the best of the lot - he has been exceptional both in terms of taking wickets and checking the runs. The next two are Australians, and their economy rates are slightly surprising, since both can be scatterguns at times.

Among the spinners there are eight with an economy rate of less than seven. The exceptional Vettori leads the way - he hasn't always been among the wickets in Tests and ODIs, but in the shortest format he has 31 wickets in 22 games, and he is the only bowler to have an economy rate of less than 5.50 in this format (with the qualifications mentioned). Ajantha Mendis has an economy rate of less than six too, in a list dominated by bowlers from the subcontinent. Johan Botha, the South African offspinner, is the only one apart from Vettori who isn't from the subcontinent.

Plenty has been written and said about the Duckworth-Lewis target of 60 in six overs for West Indies in their match against England. Paul Collingwood's angst was understandable, and his point was a valid one: on the 22 previous occasions that teams have scored more than 190 after batting first in a Twenty20 international, 19 times they've finished victorious. There were two defeats - for West Indies in the first match of the 2007 World Twenty20, and for Sri Lanka against India in Mohali last year - and a tie for New Zealand against Australia in Christchurch earlier this year.

Chris Gayle admitted after the match that his decision to chase stemmed from the possibility that the rain rule might come into play; the other thing he did right was to ensure that West Indies didn't lose any wicket when the interruption eventually came. That - and not the fact that they scored 30 runs in 2.2 overs - ensured that the overall target when play resumed became 60 in six. Even if West Indies had been, say, 10 without loss in 2.2 overs, the target would have been 60; however, if they'd lost two wickets in those two overs, the target would have gone up considerably, to 71. To calculate revised targets, the Duckworth-Lewis system only takes into account overs lost and wickets in hand at the time of the interruption; the runs on the board are immaterial in calculations.

One suggestion that has come up is to insist on a minimum of 10 overs for a valid result. If only 10 overs had been lost instead of 14, West Indies would have been set 101 for victory if they'd lost no wickets at the time of interruption. That would surely have been a tougher ask, since they'd have had to maintain a run rate of 10 over a longer period (which also justifies the demand that the target in six overs should have been higher). If they'd lost two wickets before the interruption, the target would have risen to 110.

The lesson to all teams, thus, is to keep as many wickets in hand as possible if there's rain in the air. In the case of an interruption, those wickets will be worth plenty.