These two players are the only cricketers from this country to have achieved this feat. The feat in question has less to do with overall cricketing talent and more to do with their importance to the team.
Q1: Is the team from the subcontinent? No
Q2: Is it a batting feat? No - it is not a statistical feat
Q3: Does it have anything to do with captaincy? No - though one of the players did captain his team
Q4: Is the country England, South Africa or Australia? Yes
Q5: Is the country Australia? Yes
Q6: Is it to do with test cricket? Yes
Q7: Were the players selected in the test side as batsmen? No - only one of them
Q8: Did the player that was captain play post 1960? Yes
Q9: Is one of them Brian Booth? No
Q10: Is it to do with the amount of wins the team has acheived when the two cricketers are in the team? No
(Hint: The feat has to do with how long their test careers lasted, and in what era)
Q11: Did the captain play post 1970s? Yes
Q12: Did the captain play post 1980? Yes
Q13: Did the captain play post 1990s? No
Q14: Is it one of these three? GSC, Yallop, Kim Hughes. No
Q15: Was he captain in more than 5 tests? Yes
(Hint: Questions 8, 11, 12, and 13 are the key to the actual feat - think decades)
Q16: Does the feat consist of having a career that spans three decades (eg. starting in 1970s, playing through 80s, and into 90s, for example)? Yes
Q17: Is one of the players Allan Border? Yes