As things stand at the moment, Shikhar Dhawan is the frontrunner to open the batting for India in the 2015 World Cup. However, the question over his opening partner has already evoked a furious debate, with opinion divided over who between Rohit Sharma and Ajinkya Rahane will be the better option.

Rohit was clearly the frontrunner till the end of last year year, but a finger injury in England cut short his tour and gave Rahane an opportunity which he grabbed, scoring 106 off 100 balls in the fourth ODI of the series at Edgbaston. Since getting the chance to open the batting on that England tour, Rahane has scored two hundreds and a fifty in ten innings, averaging 43.30 at a strike rate of 89.

However, in his first international innings since that injury, Rohit swung the scale back in his favour with a scarcely believable score of 264 in Kolkata, tearing the Sri Lankan bowling apart in making the second-highest score in all List A games. He was dropped on four, but made the most of that opportunity, while Rahane started more fluently and made 28 at faster than a run a ball, but couldn't kick on and get a big score.

The table below compares the ODI stats for Rohit and Rahane, and in almost all aspects Rohit is ahead, in some cases by a substantial margin. Rohit's overall ODI average is eight more than Rahane's, while his average as opener is 17 more than Rahane's - it went up from 43.74 to 49.33 in just one innings. When opening at home, Rohit averages 93 at a strike rate of 110 (up from 74 at a rate of 99.70 before the Kolkata innings) compared to Rahane's 30.52 at a strike rate of 77.

Had the 2015 World Cup been held in India, there would've been an overwhelming case in favour of Rohit Sharma, based on the stats available. When batting at home, Rohit converts his starts, and goes on to make big scores: out of 12 innings as opener in India, he has touched 20 seven times, and on six of those occasions he has scored more than 70. His three centuries are 264, 209 and 141 not out. Rahane, on the other hand, has fairly ordinary numbers in India, and one of his problems has been the tendency to get starts but not convert them: nine times in 17 innings he has scored 20 or more, but only thrice has he gone past 50, and his one century was a small one - 111, against Sri Lanka earlier in the series. In innings when Rohit scores 20 or more as an opener in India, he averages 148.33 at a strike rate of 116; Rahane, in similar innings, averages 51.33 at a strike rate of 86.

However, the one parameter when Rahane's stats look better than those of Rohit's is when opening the batting outside India. The averages are similar, but Rahane scores his runs much faster - he has a strike rate of 84, compared to Rohit's 66. Both have had some success in England, but Rohit has struggled in South Africa - 66 runs in five innings - and has been average in New Zealand - 145 runs in five innings. (Rahane hasn't opened the batting in New Zealand or South Africa, but in six innings in other positions in these countries, he has scored only 59 runs.)

ODI stats for Rohit Sharma and Ajinkya Rahane
  Player Inngs Runs Average Strike rate 100s/ 50s
Overall Rohit 119 3743 38.19 81.03 5/ 23
  Rahane 41 1228 29.95 78.01 2/ 7
As opener Rohit 40 1776 49.33 83.93 3/ 11
  Rahane 30 960 32.00 80.20 2/ 5
As opener - at home Rohit 12 696 93.00 110.58 3/ 3
  Rahane 17 519 30.52 77.23 1/ 2
As opener - away+neutral Rohit 28 846 32.53 66.35 0/ 8
  Rahane 13 441 33.92 84.00 1/ 3

The tables below further elaborate on the differences between Rohit the ODI batsman at home and Rohit the ODI batsman overseas, and also compares his stats with those of Rahane's. At home, Rohit tends to make up for slow starts by dramatically increasing his rate of scoring boundaries later in his innings, exactly like he did in his stunning innings of 264: he went from 200 to 250 in 15 balls, but his first 50 took 72 balls. When playing at home, Rohit hits a four or a six every eight balls, though in the first 15 overs he hits one every 11 balls. When playing overseas, Rohit's boundary rate over his entire innings drops to one every 15 balls, which is almost half the rate of his home innings. In fact, his overall boundary-scoring rate is marginally lower than his corresponding rate in the first 15 overs, whereas at home he is able to get more boundaries after the first 15.

In overseas games, Rohit also tends to get dismissed far more often within the first 15 overs: at home, he has scored 366 runs and been dismissed seven times in the first 15, but overseas he has scored 767 runs and been dismissed 30 times, giving him an average of 25.56. Rahane, on the other hand, averages 38.50 in the first 15 overs (385 runs, ten dismissals), and has a better scoring rate, primarily because of a higher boundary frequency.

Rahane's poor conversion rate is a worry, but a comparison of overseas stats shows him in a better light than Rohit. On the other hand, Rohit has more ODI experience, and with runs and matches behind him, he could well turn around his relatively poor overseas numbers. At the moment, though, the jury's still out on who should open the innings for India in ODIs in the 2014-15 overseas season.

Dots and boundary stats for Rohit and Rahane in home ODIs
  Runs Average Strike rate Dot-ball % Balls per 4/6
Rohit - entire inngs 1434 68.28 99.50 48.47 8.00
Rahane - entire inngs 519 30.52 77.17 57.29 10.84
Rohit - first 15 overs 366 52.28 68.67 63.98 11.10
Rahane - first 15 overs 350 29.16 70.00 63.20 11.11
Dot and boundary stats for Rohit and Rahane in away ODIs
  Runs Average Strike rate Dot-ball % Balls per 4/6
Rohit - entire inngs 2309 32.06 72.50 54.36 15.28
Rahane - entire inngs 709 29.54 78.50 56.65 11.14
Rohit - first 15 overs 767 25.56 60.00 67.68 14.52
Rahane - first 15 overs 385 38.50 71.00 64.39 10.84

S Rajesh is stats editor of ESPNcricinfo. Follow him on Twitter