There is often a significant difference in how batsmen perform in different innings. This is apparent when we look at those with the highest averages in Tests (for those who have batted in at least 20 innings).
Data is correct up to April 3, 2018. The ICC XI v Aus Test of 2005 is not counted.
First we look at the averages for Tests as a whole, for a minimum of 20 innings batted across innings;
Highest batting averages in Tests (50 and above):
You do not need to be reminded about the man with 99.94. The next two are also well known in recent years. Some, like Kambli, are lucky to scrape through. Other contemporary players listed above include Kohli, Root, Younis Khan, de Villiers, Pujara and Williamson.
Most of those who are generally regarded as great batsmen are here-even though some like H Sutcliffe, GE Tyldesley and CA Davis never made a double century.
Now we look at the different innings. The 20-innings cutoff is applied in each case.
Highest batting averages in first innings of Tests (55 and above):
Bradman and Steve Smith are still in the top 3, but then there is considerable variation. Hassett and Azhar Ali averaged less than 50 in all innings but did much better in the first innings. Voges, Graeme Pollock and Headley did not play enough Tests. Barrington and Weekes seemed to have particularly relished batting in the first innings.
Contemporary players here include Steve Smith, Azhar Ali, Pujara, Ross Taylor, du Plessis, Root and a few others.
Moving on to the second innings.
Highest batting averages in second innings of Tests (55 and above):
Bradman is still at the top, followed relatively closely by Kohli. Other contemporary players include Steve Smith, Williamson, Root, de Villiers, Younis Khan and AN Cook. Tendulkar just scrapes through the 55-mark, some distance behind Gavaskar who did not do too well in the first innings.
Now to the third innings.
Highest batting averages in third innings of Tests (50 and above):
Bradman now drops out of the table altogether, with May and Kallis taking the two top spots. Here the differences between the top players are comparatively smaller. Contemporary players here are headed by Amla and Azhar Ali.
Finally the fourth innings, where survival skills are particularly important:
Highest batting averages in fourth innings of Tests (40 and above):
As we can see, it is as difficult to average 40 here as it is to average 50 overall. Boycott, Gavaskar and Hobbs are bunched together at the top. And some like Bradman did not need to do much in the fourth innings as they and their teams generally scored enough in the first and second innings. Some, such as Ranatunga, Misbah and Hutton did not even score centuries in the fourth innings and probably benefited by a number of not-out innings.
Contemporary players here include Younis Khan, AD Mathews, Misbah-ul-Haq, Warner, Ross Taylor and Mohammad Hafeez.
Comparison of centuries made in different innings will be taken up next.