Complex sentence: When he returned to Australia, Masters rejoined Balgownie in their triumphant, undefeated 1921 championship side, and played for Australia, eventually turning out 22 times for the national team in both "A" and "B" internationals.
Split into simpler sentences: When he returned to Australia, Masters rejoined Balgownie in their undefeated 1921 championship side. Masters played a total of 22 times for the national team in both "A" and "B" internationals.