When the national team played its first international game after the Second World War in December 25 of the year 1944, Arsène Vaillant, playing for White Star, was in the line-up as offensive midfielder. Six years later, he would make a second debute for the national team, this time as a defender.
Arsène Vaillant was athletic person. He was good at football and ... basketball. He prefered being a goalkeeper, but his explosive shot and his intelligence made him an offensive midefieler. He was playing for the Brussels' club White Star and was sometimes put on several other positions on the field because of his flexibility.
After a conflict with the direction board in 1947, he ended his career as a professional player and he went to a local amateur club. One year later, Sporting Anderlecht noticed the player and asked him to join the club. Vaillant agreed and was lined-up next to Mermans as a striker. In exchange, Anderlecht gave Polyte Vanden Bosch and goalkeeper Raymond Ausloos to White Star. Arsène Vaillant was coached by the Irish trainer Ernest Smith.
In the season '48-'49, defender Jean Weyns (left-back position) got injured and Vaillant replaced him. He got injured himself, but returned three weeks later and was positioned in the defense again. He left such a good impression, that he was again selected for the national team. This time as a defender. In the national team, he played together with his Anderlecht team mates Rie Meert and Rik Matthys. He collected 11 A-caps and won 5 Belgian titles. In 1955, he ended his career and became commentator for the RTBF.