1. A wicket keeper who played his only Test against New Zealand in the 1970s. He scored 7*, took two catches and conceded 16 byes.
A Pakistani called Shahid Israr. Definitely fits.
2. A modern great with 26 Test centuries to his name, but an average of only 36 against South Africa.
Rahul Dravid - only two folks with 26 tons, and his average fits
3. A between-wars bowler whose only Test was the match before the one in which the main answer made his debut. He took no wickets, returning 0-60 and 0-12, but scored 8 and 44 with the bat.
Otto Nothling (Australia)
4. A 1980s batsman who scored over 4000 Test runs, including centuries against West Indies when the rest of his team kept folding, and memorably won an ODI with a lot of runs off the last over.
Allan Lamb. Smashed a piled from Bruce Reid. Scored a few 100s against WI. Could it be anyone else?
5. A current all-rounder who has a century and a six-wicket haul in different matches on tour in Australia, but has yet to reach 100 wickets and 2000 runs.
Dwayne Bravo - Took 6 in Adelaide in late 2005, and 100 in Hobart on the same tour. 70 wickets and 1800 odd runs.
6. A batsman and part-time bowler more usually thought of as an ODI player, he only averaged 28 with the bat, though he made three Test centuries, the highest being 123 against Pakistan.
Russel Arnold. The numbers fit and he averaged 35 in ODIs.
7. A 1990s pace bowler who took 160 wickets but is more usually remembered for some lengthy stonewalling innings at number 11, including 14* in a last-wicket partnership of 106 against England.
Danny Morrison (NZ) definitely, batting with Astle
8. A current bowler who has 123 Test wickets to his name – although he says his name changes to something German when he gets out on the field.Andre Nel.
So the answers spell Sir Donald Bradman.
Although I can't see how it is linked to the first cryptic clue about Azhar and Key.
Also, Nothling made his debut in the Second Test.
Bradman debuted in the First Test, failed, was dropped and came back in the Third Test and made his first Test century