Bowlers win Test matches. A corollary of the moth eaten adage is that fast bowlers win Tests outside the subcontinent. India are yet to win a series in South Africa and thereby hangs a tale. However, the expansion of India's fast bowling reservoir has injected optimism that the team can finally overcome the 25-year hoodoo.

Undeniably, India's quintet chosen for the tour are a promising group of pacers, who have shown drastic improvement since the previous cycle of overseas drubbings. The earliest manifestation of their progress was witnessed during the four-nil routing of England, where both Mohammed Shami and Umesh Yadav out bowled the pair of James Anderson and Stuart Broad. Then, in the subsequent series against Australia, which was played on a variety of pitches from Pune to Dharamsala, Yadav was comfortably the best pacer on view with 17 wickets. The highly rated Josh Hazlewood, in comparison, was a distant second with just nine scalps. In four combatively contested Tests, where balance shifted like a pendulum, and there was little to choose between the spinners, Yadav's performance was the clincher for India.

This situation, however, isn't unprecedented. Traditionally, India's pacers have been more successful on benign surfaces at home, rather than pitches outside the sub-continent, that are presumably tailor-made for their ilk. The likes of Javagal Srinath, Ishant Sharma and even Kapil Dev have better records in India. Zaheer Khan is perhaps the lone exception to this curious rule. That too, only marginally. The major cause for this glaring disparity is not the lack of skill or adaptability, but the paltry returns of the batsmen, who have often been reduced to puny dwarfs overseas, thereby rendering the attack significantly impoverished.

Anil Kumble, India's greatest match winner during the 1990s, and now R Ashwin have always had runs to play with, in addition to helpful conditions at home. In both cases, it has meant that their captains have been able to set them attacking fields for prolonged periods which have resulted in wickets, and consequently victories. In fact, Kumble's second wind, that saw him achieve far greater success abroad serendipitously coincided with the collective evolution of a batting line-up that had consistently begun to stand-up to challenges overseas. The historic wins in Leeds and Adelaide, that were built around huge first innings totals, serve as resounding reminders of that successful template.

That's a luxury the current crop of pacers seldom had the last time the team was on the globe-trot, given that only three batsmen averaged over 40 in 13 Tests. Often, and perhaps most notably at Manchester in 2014 - where the series was still hanging by a slender thread - MS Dhoni was forced to spread the field prematurely due to lack of runs in the first innings. This was despite the fact that his bowlers had England on the mat at 170 for six. But England were already 18 ahead, and the absence of catching fielders coupled with the easy availability of singles allowed the pair of Joe Root and Jos Buttler to eke out a partnership of 134. That period of play sealed India's fate in the series, but the sails of the windmill had swung momentum England's way when the tourists were abjectly skittled for 152.

Similarly, only a cricket buff stricken with amnesia could have forgotten that the most common pattern to emerge from India's infamous streak of eight Test losses in England and Australia (2011-12) was that only twice did they manage totals in excess of 300 in 16 innings. Nothing changes in the South African context either. India's previous failings in the country have owed much to the fact that only Sachin Tendulkar and VVS Laxman averaged over 40 over a large enough sample size. So while the buzz word is 'wickets' as India embark upon their South African sojourn, It is India's vaunted batting unit led by Virat Kohli that might determine if the talented pace bowling quintet is able to bowl them to an elusive series win