3 Tests - 188 runs at 31.33; 7 wickets at 53.85
1 Test - 21 runs at 10.50
Simpson announced his retirement during the 1967-68 series against India, but was brought back for the final Test of the series for a farewell at the SCG under the new captain, Bill Lawry. In the one-off occasion, the 31-year-old Simpson made 7 and 20. It wasn't quite his last Test, though. Ten years later, he was drafted back in to captain an inexperienced side during the World Series Cricket split.
9 Tests - 607 runs at 40.46; 2 wickets at 27.00
Chappell stood down from the captaincy at the end of Australia's successful Ashes tour of 1975, but remained available for selection under the new leader, his brother Greg. He had made 192 in the final Test at The Oval, so his form was not an issue. Two matches into his post-captaincy career, Chappell made 156 against a fearsome West Indies attack led by Andy Roberts and Michael Holding at the WACA, although Australia lost by an innings. He retired after six Tests, but made a comeback four years later, after World Series Cricket, and ended his career with 75 and 26 not out against England in the Melbourne Test of 1979-80.
5 Tests - 364 runs at 72.80
Chappell resigned from the captaincy after Australia's 1982-83 Ashes victory, although he returned to lead the team for a one-off Test in Sri Lanka later that year. But by the next Australian summer, Kim Hughes was in charge and Chappell played one final series, against Pakistan. He made two big hundreds in the five-Test series and finished his career with 182 in the final Test at the SCG, when at the age of 35, he farewelled international cricket alongside his colleagues Dennis Lillee and Rod Marsh.
24 Tests - 1691 runs at 42.27
Yallop is an extraordinary case; as captain of Australia's weakened Test team during the World Series Cricket days, he was in charge for only seven matches before Hughes took over, and then the rebel players were welcomed back into the fold. He played on for five more years under Greg Chappell and Hughes, and played some fine innings, including 268 against Pakistan at the MCG in 1983-84, before his first-class career ended with the rebel tour of South Africa.
2 Tests - 2 runs at 0.50
Hughes was an on-again off-again captain during and after the World Series Cricket era, including when Greg Chappell chose not to make tours to England and Pakistan. His full-time tenure as captain, after Chappell's retirement in 1983-84, ended with a tearful resignation following the Gabba loss to West Indies in 1984-85. Hughes played on in the next two Tests of the series but his scores were 0, 2, 0 and 0, and he did not represent Australia again. Hughes was the last captain of Australia until Ricky Ponting to play on after handing over the leadership. Ponting moves into his post-captaincy career in a much more positive frame of mind.