[4] He played football for the Boys' Brigade team based at Dalry church, from where he and Peter Barrett followed Bobby Russell to Penicuik Juniors.
[8] He was joined soon afterwards by his former colleagues, manager David McLean believing that "the best value could not be got from the winger until they had the generalship of Barrett and the resourceful feeding of Russell" to complete the left side of his team.
[5] Early in that season, a Courier match report highlighted the danger stemming from Edgar's crosses despite his being marked by the best of the opponents' defenders.
[9] According to the Evening Telegraph, Edgar's return from six weeks out with a knee injury (sustained in East Fife's Scottish Cup draw at Kilmarnock[10]) "made all the difference" to his team in a 1–0 win against Dunfermline Athletic: "he was in dazzling form, and attracted all eyes by his brilliant play.
Against Johnstone in early November, the Courier praised his trickery and the quality of crossing and shooting,[12] though three weeks later against King's Park, "his finishing left a good deal to be desired",[13] and against Arbroath in December he twice missed an open goal.
[16] In his last appearance for East Fife, in mid-October, Edgar crossed for his team's first goal and scored the second in a 2–1 win at home to Alloa Athletic.
[3] He marked his debut, in a 7–1 defeat of Third Lanark, with two "beautifully taken" goals,[22] and went to make seven appearances, without scoring again, as Airdrie finished runners-up in Division One.
The opening goal was fortuitous: with the Arthurlie goalkeeper well placed to take Edgar's cross, a defender touched the ball into his own net.
[29][30] In 1928, Edgar was listed as open to transfer by Hearts at a fee of £300, which would not become payable unless the player joined another Football League club, whether in Scotland or England.
[39] He also played in all five of Darlington's matches in the 1933–34 Third Division North Cup as they progressed to the final at Old Trafford and beat Stockport County 4–3 with a last-minute goal from Dan Cassidy.
[46] Although the Courier reported in the 1937 close season that Edgar "would not be averse to a return" to Scottish football,[47] he and former Darlington teammate Jerry Best were at Hexham, also of the North-Eastern League, in 1938.
In 2001, John Edgar told the Northern Echo that as a young man he had had the opportunity to sign for Sunderland, but his father strongly advised him to continue his education rather than taking the risk of a career in professional football.