Although Aston's international career with England was now behind him, he would play his part in a representative British Isles team, when he was selected to become part of Bill Maclagan's British Isles team on their 1891 tour of South Africa. On the hard grounds of South Africa, Aston was a revelation, possessing not only a massive frame, recorded as 15 stone, but also impressive speed. Aston played in all twenty games of the tour including the three Tests, amassing an incredible 30 tries in total. He scored a try in two of the Test matches, the first in Port Elizabeth and the final Test in Cape Town. If it wasn't for the peculiar scoring system of the time, he would have ended the tour as the top Test points scorer, but his two tries were surpassed by two conversions by Arthur Rotherham.