The doosra effect

The decision to have Saeed Ajmal bowl the last over in Pakistan's heartbreaking semi-final loss against Australia was a bad one, said Sohail Tanvir, his team-mate at Rawalpindi. "I have played a lot with Saeed and he is a sort of bowler who struggles against the left-handers and in pressure situations, it was not a good idea to give him the final over when there were two left-handers at the crease," Tanvir said. Stats bear out the first part of his argument, at least in Twenty20 internationals: Ajmal has conceded 164 runs in 140 deliveries and taken seven wickets against left-handers; against right-handers he has taken 24 wickets in 317 balls and conceded only 312 runs.

Having played with Ajmal for some time, Tanvir probably knew something most probably didn't. Logically, you'd expect an offspinner to trouble left-handers more than right-handers, since the offbreak spins away from the left-hander and is hence harder to hit.

Which raises a broader question: do offspinners generally prefer bowling to left-handers, or has the invention of the doosra made them an equally potent threat against right-handers as well? And how have left-arm orthodox spinners fared against the two types of batsmen, given that none of them bowl the equivalent of the doosra?

Let's start with Tests. Stats from the last eight-and-a-half years suggest that offspinners have generally done better against right-handers - now that's a finding that goes against conventional wisdom. On the other hand, left-arm spinners too do better against the righties - they concede 10 runs more per wicket when bowling to left-handers.

In ODIs, offspinners seem to have no preference - their average and economy rate against right- and left-handers are almost the same. For the left-arm spinners, though, the difference is significant: an average of less than 33 against right-handers balloons to more than 46 against lefties, and at a higher economy rate too.

Offspinners and left-armers in ODIs since 2002 (Qual: 300 balls bowled to each type of batsman)

Bowler type	Batsman type	Wickets	Average	Econ rate	Strike rate
Offspinners	Right-handers	910	35.37	4.47	47.46
	Left-handers	407	34.50	4.42	46.82
Left-arm orthodox	Right-handers	852	32.83	4.30	45.81
	Left-handers	221	46.48	4.71	59.24

All ODI numbers only include games involving the top 10 teams.

As you'd expect, Muttiah Muralitharan dominates the list of the offspin bowlers, with a haul of 410 wickets in Tests since 2002. What's far more surprising, though, is the difference in his stats against the two types of batsmen. He has dominated most right-hand batsmen, but his average against left-handers goes up to 27.59. And since the stats begin from 2002 (Cricinfo doesn't have complete ball-by-ball data for the years prior to this), these numbers don't even include Brian Lara's unbelievable series against him in November 2001. (They played again in a series in 2003, in which Lara scored 87 from 182 balls off Murali and was dismissed once.) Michael Hussey (100 runs, no dismissals), Stephen Fleming (171 runs, no dismissals) and Shivnarine Chanderpaul (107 runs, one dismissal) are some of the other left-hand batsmen who've shone against him. Murali has had his share of wins against lefties - Sourav Ganguly has been dismissed seven times in scoring 90 runs during this period - but generally they've done reasonably well against him.

Among other bowlers, Harbhajan Singh's stats are pretty even against left- and right-handers, but Graeme Swann and Nathan Hauritz have both done better against lefties, with the difference in Swann's case being huge. Pakistan's Saqlain Mushtaq was a master of the doosra, and that surely helped him dismiss right-handers cheaply, especially during a period when few other bowlers had mastered the delivery.

For left-arm spinners, Daniel Vettori's stats tell the story: his numbers against right-handers are very good, but against left-handers he hasn't been so impressive, averaging almost 42 runs per wicket. Adam Gilchrist averages 103 against him, Chris Gayle 164, and Kumar Sangakkara 125, while Gautam Gambhir scored 102 against him without being dismissed.

Monty Panesar and Shakib Al Hasan both have much better numbers against right-handers, while the same can be said of Sri Lanka's Rangana Herath as well. Clearly, left-arm orthodox spinners haven't met the challenge of bowling to left-handers as well their right-arm counterparts have the challenge of bowling to right-handers.

Like in Tests, in ODIs too Muralitharan has done much better against right-handers than against lefties. Gilchrist (141 runs in 158 balls, out twice), Suresh Raina (91 in 99, out twice), and Simon Katich (77 in 94, no dismissals) have been some of the left-handers who've handled the Murali threat in style. MS Dhoni and Ricky Ponting have excellent numbers against Murali as well, but one of the right-handers who has struggled against him is Virender Sehwag: in 60 balls he has been dismissed four times, scoring 51 runs. Harbhajan has better stats against right-handers as well, but Hauritz, Johan Botha, Jeetan Patel and Swann are among those who'd much rather be bowling to left-handers. Is it a mere coincidence that none of them is known to possess a deadly doosra?

Among the left-arm orthodox spinners, the stats are far more consistent, with all of them preferring to bowl to right-handers. The difference is significant for Vettori, just like it is in Tests. Ponting and Andrew Symonds have both been dismissed by him six times at averages of less than 40. Michael Bevan, on the other hand, has scored 83 runs against him without being dismissed once, while Michael Hussey (154 runs in 221 balls, dismissed once) and Chanderpaul (94 in 110, dismissed once) have also handled him extremely well. For some of the others, like Bangladesh's Shakib and Abdur Razzak, the difference in averages is even greater.

Left-arm orthodox spinners v right- and left-handers in ODIs

Bowler	Right - wickets	Average	Econ rate	Left - wickets	Average	Econ rate
Daniel Vettori	137	27.78	3.83	44	37.40	4.20
Sanath Jayasuriya	83	38.30	4.62	19	45.00	4.70
Abdur Razzak	74	24.09	4.27	24	45.66	4.75
Shakib Al Hasan	62	26.17	3.87	13	60.23	4.83
Mohammad Rafique	55	32.27	3.89	21	54.28	5.04
Yuvraj Singh	54	38.48	4.99	10	57.90	5.39
Ray Price	39	31.84	3.66	14	52.57	4.26
Ashley Giles	34	35.64	4.14	13	37.69	4.36
Nicky Boje	33	32.51	4.34	15	33.66	4.72

All ODIs only include matches involving the top 10 teams.