India have always featured prominently in any discussion about spin bowling, but never was this emphasis on spin greater than in the 1960s and 1970s, when four of their most celebrated slow-bowling exponents played together. There were high-quality spinners from India before - Subhash Gupte scalped 149 wickets at 29.55, and was rated better than Shane Warne by no less a player than Garry Sobers; Vinoo Mankad snared 162 at just over 32 and also contributed mightily with the bat; while Bapu Nadkarni was the king of thrift, taking 88 wickets and conceding 1.67 runs per over. However, when Bishan Bedi, Bhagwat Chandrasekhar, Erapalli Prasanna and S Venkataraghavan broke into the team in the 1960s, they established such a hold over the Indian bowling attack that for the next decade and more they became the core of the bowling unit, in all countries and conditions, to such an extent that India's seam and swing bowlers became almost redundant.

It was a diet by spin for opposition batsmen, and yet there was plenty of variety in the menu to choose from. Bedi was the classical left-arm spinner with a smooth action and fantastic deception; Chandrasekhar was as unorthodox as Bedi was orthodox, bowling sharp topspinners, googlies and legspinners at almost medium pace; Prasanna and Venkataraghavan were both offspinners, but while Prasanna was guileful and crafty, Venkat was accurate and relentless. Together they defined the Indian bowling attack, on turning tracks at home and in seaming conditions abroad.

The overall stats for three of those four spinners are pretty similar: Bedi led in terms of matches played, wickets taken and bowling averages, but Chandrasekhar and Prasanna weren't far behind. Venkat's stats suffered in comparison to the other three - he averaged less than three wickets per Test - but his career economy rate of 2.27 shows he was tough to score off.

Chandrasekhar's average was slightly higher than Bedi's, but his strike rate was easily the best among them all. At his best he was probably the most unplayable of them, and he was the only one among the four who averaged more than four wickets per Test. India didn't win too many overseas Tests during that time, but when they did, Chandrasekhar had a significant role to play in each: in five overseas wins he took six in an innings five times, and averaged 17.14.

Apart from Venkat, the other spinners did pretty well overseas too. Chandrasekhar, Bedi and Prasanna all averaged less than 34 in away Tests, which is significantly better than India's top spinner today: Harbhajan Singh's away average is 38.83. The only bowler among the quartet who didn't have much success abroad was Venkat, averaging more than 44 and taking only one five-for in 25 Tests.

Between December 31, 1966 and the end of 1978, India played 68 Tests, of which at least three of these four spinners played in 55. (In one Test, against England at Edgbaston, all four played but India lost by 132 runs.) In the 55 Tests, India's record read thus: won 14, lost 25, drew 16. It doesn't look all that imposing, but it's a whole lot better than India's Test record before they came along: in the 12 years before these four started playing together, between the beginning of 1955 and the end of 1966, India had won only seven out of 56 and had lost 19. The win-loss ratio thus changed from 0.37 to 0.56, an improvement of 51%.

Among those 14 wins were some pretty significant ones. In 1971, they won a Test in the West Indies for the first time, and followed that with their first win in England. On both occasions they won the series. The win in Port-of-Spain in 1976 is remembered mostly for the run-chase of 403, but the spinners did their job too, with Chandrasekhar taking eight wickets in the match and Bedi five. In Auckland in 1976, Chandrasekhar and Prasanna combined to take 19 wickets in the match as India won by eight wickets. And then there were the two wins in Melbourne and Sydney in 1977-78 - albeit against a depleted Australian team - which brought India back in the series after they lost the first two Tests. Overall, of the 14 Tests that India won, six were overseas.

During this period when the spinners were in full flow, the role of pace in the Indian bowling attack was reduced to a bare minimum. In the 68 Tests between 1967 and 1978, spin contributed 766 wickets, an average of more than 11 per match. No team came close to that average, with Pakistan's 6.46 being the next best. Spin also contributed almost 78% of the wickets that Indian bowlers took during this period.

And in the 55 matches when at least three of them played together, their numbers were pretty identical to those listed above - an average of about 11 wickets per match and 30 runs per wicket.

The four Indian spinners were among the best during this period, but there were a few others who were in that bracket. England's Derek Underwood led the way in terms of both wickets and averages, taking 264 at an excellent rate of 24.34 runs per wicket. Bedi was next in terms of wickets, but Ashley Mallett, Australia's offspinner, had excellent numbers too, averaging less than 28 for his 125 wickets. West Indies' Lance Gibbs was the other offspinner in this list, taking 172 wickets in 47 games.

Playing four spinners in the same XI wasn't a luxury India could afford, though, so three in the side was the staple. Here's a look at how the spinners and the team fared when various combinations of three spinners played.

Bedi, Chandrasekhar and Prasanna
In the 24 Tests that Chandrasekhar, Bedi and Prasanna played together, India won seven and lost 12. Four of these wins were in two five-Test series when India fought back from 0-2 deficits to draw level, only to then lose the final match. The trio helped India beat West Indies in Kolkata and Chennai in the 1974-75 series, before they lost the last match in Mumbai, while that sequence of results was repeated in Australia in 1977-78 - wins in Melbourne and Sydney to draw level, followed by defeat in Adelaide to lose the series.

Among the three bowlers, Chandrasekhar and Bedi had identical numbers, taking just over 100 wickets at excellent averages. Chandrasekhar's best was in that Melbourne game, when he took figures of 6 for 52 in each innings to finish with match figures of 12 for 104 - his best in his 58-Test career. Bedi took two six-fors as well, but in two matches, and with hugely contrasting results - 6 for 71 against England in Bangalore in 1977 (a match in which Chandrasekhar took six as well), and 6 for 226 in the Lord's drubbing in 1974.

Among the three, the bowler with the least impressive stats in these 24 Tests was Prasanna, with only 61 wickets at an average of 40. His only five-for was against West Indies in that Chennai Test in 1974-75. And six times he finished wicketless in an innings despite bowling 20 or more overs.

Overall, in the 24 Tests that all these spinners played, they accounted for 266 out of 346 wickets taken by the Indian bowlers - a percentage of 76.88.

Bedi, Chandrasekhar and Venkataraghavan
Bedi, Chandrasekhar and Venkat played together 18 times, and of those Tests, India won four and lost seven. A couple of those wins were especially famous: in 1971 at The Oval, India won a Test, and a series, for the first time in England; and in Port-of-Spain in 1976, India chased down 403, at the time the highest fourth-innings total in a win.

Among these three, Chandrasekhar was again the bowler who was the most influential in the two wins: at The Oval his 6 for 38 destroyed England in their second innings, while in Trinidad his 6 for 120 kept West Indies down to a manageable 359 in their first innings. Overall, though, Bedi was the most successful in these 18 Tests, with 85 wickets at 24.96. Venkat played a strictly supporting role in most of these matches, taking only 39 wickets at more than 40 each. Overall, these three bowlers took 208 out of 262 wickets taken by all Indian bowlers in the 18 Tests.

Bedi, Prasanna, Venkataraghavan
Prasanna didn't do too well when he played alongside Bedi and Chandrasekhar, but his performances lifted when Venkataraghavan was around. In 13 Tests that he played with Venkat and Bedi, Prasanna took 61 wickets at less than 28. Venkat himself didn't do too badly: though he took only 41 wickets, his average was the best among the three. Bedi was relatively less successful in terms of wickets, but his economy rate of 2.04 runs per over was the best among the three.

In these 13 Tests, India won only two and lost seven. One of the wins was against West Indies in Port-of-Spain in 1971 - Sunil Gavaskar's debut Test. The three bowlers together picked up 145 wickets out of 181 that the Indian bowlers took - a percentage of 80.11.

And finally, a look at the batsmen who excelled against India during this period. No one dominated them like Zaheer Abbas on India's tour to Pakistan in 1977-78. In five innings his scores read thus: 176, 96, 235*, 34*, 42. In fact, that series hastened the end for the three spinners who played in that series: Chandrasekhar averaged 48.12, Bedi 74.83 and Prasanna 125.50. Prasanna didn't play any Tests after that, Chandrasekhar played five and Bedi six. Venkataraghavan was around for much longer - till 1983, but in his last four series he wasn't much of a force, averaging more than 50 in each of them. In fact, in his last 14 Tests he managed only 23 wickets.

The era of the four Indian spinners ended with a bit of a whimper, but while it lasted it was glorious.

(Click here for the full list of batsmen.)