The Adelaide defeat has firmly put the focus on England's batting. In four innings in this series, they have gone past 240 just once, and much of the attention has been on their two senior batsmen in the top five, Joe Root and Alastair Cook.

It is inevitable that that should happen. The rest of their top order is woefully short on experience - Mark Stoneman, James Vince and Dawid Malan had a combined total of 15 Tests coming into this series - and Root and Cook are both high-quality batsmen who have plenty of Ashes experience. That neither has stamped his authority yet on the series is a key reason why England find themselves 2-0 down in the series, but going back further than these two Tests, it is also clear that both these batsmen have had a few problems when playing away from home.

Since the start of 2013, Root averages 44.39 in 26 away Tests, while Cook averages 36.43. In home Tests during the same period, their averages are 59.46 and 45.26. Add Jonny Bairstow to the mix (home average 44.41, away 34.45), and three of England's regulars are far more prolific at home than away. The difference between their home and away averages adds up to almost 34 runs.

Home-away stats for Root, Cook, Bairstow since Jan 2013
Batsman Home-mat Ave 100s Away-mat Ave 100s
 Joe Root  35  59.46  10  26  44.39  3
 Alastair Cook  35  45.26  4  27  36.43  4
 Jonny Bairstow  23  44.41  2  19  34.45  1

To be fair to Root, his average of 44.39 is pretty respectable by away standards, though it does pale when compared to his home numbers. Virat Kohli's career away average is 45.13, and Kane Williamson's is 46.88 (though in the last five years both average more than 50 overseas, as does Steven Smith).

What hurts Root, though, is his conversion rate in away games. Much has been spoken and written about his inability to convert fifties into hundreds, but at home he doesn't do too badly on that front: in 62 innings in England since the start of 2013, he has hit ten hundreds, which is one every 6.2 innings. The problem is in away matches - he has three centuries in 50 innings, which converts to a shocking ratio of a hundred every 17 innings, nearly.

The table below lists the top eight run-getters in away Tests in the last five years. (The UAE has been considered as home for Pakistan players, and away for all the other teams.) Root's average is fifth among these eight batsmen, while his median score of 27.5 is third among them. The median indicates Root's consistency, in that half of his 50 innings have yielded at least 28, while Kohli, despite having a higher average, has a median of only 25. Smith's average is almost 12 runs higher than Root's, but his median is a relatively low 30, which means in half of his 57 innings he has scored 30 or fewer runs. Smith's higher average is because of his tendency to get bigger scores - he has six innings of 125-plus, while Root has just one.

Root's rate of scoring hundreds, though, is abysmal. That is the one aspect in which the others on that table - even Cook - have done better. It's all right to say that Root goes past 50 very often and seldom gets out cheaply, but you'd want your lead batsman to make decisive contributions in a Test match more often than Root has been doing recently, especially overseas.

Top eight run-getters in away Tests since Jan 2013
Player Inns Ave Median 100s 50s Inns/100
 Steven Smith  57  56.21  30.0  10  12  5.70
 Kane Williamson  42  56.13  29.5  8  9  5.25
 Virat Kohli  41  50.53  25.0  9  4  4.56
 Younis Khan  45  46.83  21.0  7  3  6.43
 Joe Root  50  44.39  27.5  3  16  16.67
 Azhar Ali  46  44.09  25.5  6  7  7.67
 David Warner  58  39.25  24.5  6  14  9.67
 Alastair Cook  52  36.43  17.5  4  10  13.00
* Tests in the UAE taken as home games for Pakistan batsmen, and away games for batsmen from all other teams

Cook's problem, on the other hand, isn't about converting starts; it is about getting them in the first place. Twenty-eight times in 52 innings he has been dismissed before reaching 20, which is reflected in a poor median score of 17.5.

Through the first seven years of his Test career, Cook was stellar overseas, averaging 54.54 in 40 away Tests. In 12 series during this period, he averaged more than 40 in eight, and over 50 in six.

In the last five years, though, those numbers have fallen away quite drastically, with his away average dropping to 36.43. (His stats at home have stayed remarkably similar in the two periods, however: an average of 44.84 till 2012 and 45.26 since then.) The touring problem has only ben exacerbated in the last couple of years: in his last 26 overseas innings, his average has fallen further to 27.07, and he has struck only one hundred - against India in Rajkot last year.

These away numbers have also come under increased scrutiny because of England's results in overseas series in the last five years. Since the start of 2013, they have won only four out of 27 away Tests, and have lost 16. In seven series in this period before the ongoing Ashes, they have lost and drawn three each, and won only one, in South Africa in 2015-16. In the same five-year span, they have been outstanding at home, with a 21-9 win-loss ratio, and seven series wins out of ten. (The only series defeat was against Sri Lanka in 2014.) In terms of win-loss ratio, England's away record is poorer than that of all teams except West Indies, Bangladesh and Zimbabwe.

Away stats for teams since Jan 2013* (Min 10 Tests)
Team Mat W/L Ratio Bat ave Bowl ave
 India  24  8/8  1.00  36.19  35.46
 South Africa  21  7/8  0.88  27.50  28.38
 Sri Lanka  25  7/12  0.58  31.41  38.26
 Pakistan  24  8/15  0.53  29.59  33.67
 Australia  32  10/19  0.53  30.42  31.99
 New Zealand  24  6/13  0.46  32.10  40.02
 England  27  4/16  0.25  29.54  38.24
 Bangladesh  13  2/10  0.20  27.88  52.59
 West Indies  22  3/15  0.20  25.50  45.99
* Tests in the UAE taken as home games for Pakistan, and away games for all other teams

The bowling has been an issue too, largely because of the slow bowlers: England's spinners have averaged 31.75 at home in the last five years and 49.69 away. Moeen Ali averages 33.47 at home and 46.41 overseas. In the ongoing Ashes series, the difference between him and Nathan Lyon has been massive.

However, for the bowlers to bowl with the security of runs on the board, the batsmen need to get those runs regularly. In England's case, the two senior batsmen need to put their hands up and get big hundreds.

S Rajesh is stats editor of ESPNcricinfo. @rajeshstats.