At the Royal Military Academy, Ruck gained a reputation as an athlete, playing both cricket and rugby football and being a keen gymnast. On joining the Royal Engineers in 1871, he switched to association football. At this time, the Royal Engineers were among the top football teams in England, having reached the final of the first FA Cup tournament in 1872 and again two years later, finishing on both occasions as runners-up. Ruck played on the right of the half-backs and was described as a "good half-back, being a sure kick... using his weight well".