Fingleton was unable to distinguish himself on the field while at school, but after joining Waverley, he made quick progress. Fingleton trained early in the morning, before heading to the office and working in the afternoon so that the articles would be printed in the evening. He was unable to afford the club membership so a patron sponsored him. At the age of 16, he broke into the First XI of a grade team which included Test players Alan Kippax, Hanson Carter and Arthur Mailey. Australian Test captain Herbie Collins missed a match due to his work as a bookmaker, and Fingleton stood in at late notice. Under the leadership of Carter, Fingleton batted last and made 11 not out. Forced to follow on, he made 52 not out and cemented his position for the remainder of the season. Within a year, Fingleton's grade performances were being reported in Sydney newspapers. Playing on a Waverley pitch notorious for uneven bounce, Fingleton developed a style of play centred on solid defence.