Its best performance was in 1886–87, a first-round win over Drumpellier[9] - Drumpellier protested in vain against rough play and the pitch conditions, forfeiting the 10/ protest deposit[10] - giving the club a second round home tie with Cambuslang.

Ru'glen held the future finalists to a draw in what was "without a doubt the greatest surprise of the day", and even had the balance of play.

[11] Cambuslang put matters right with a 6–1 win in the replay, but Ru'glen emerged from the tie with significant credit, having played "a brilliant game", and enjoying entertainment afterwards with the victorious players, as "harmony filled up the remainder of the evening".

Its best run was to the quarter-final in 1885–86, which included beating Albion Rovers (twice after the original win was overturned, Ru'glen having turned up 25 minutes late, leaving the Rovers outside in driving rain[15]), but lost at Airdrieonians; "Athlete" of the Rutherglen Reformer had predicted an 8–0 win for the 'Onians, and he was almost correct, Rutherglen scoring a 75th minute consolation.

[17] Rutherglen twice reached the semi-final of the Glasgow North Eastern Cup, a low-grade contest which nevertheless attracted some high-class entrants.

Rutherglen drew a bye in the first preliminary round; in the second preliminary round against Annbank, Rutherglen persuaded Clydesdale goalkeeper Alexander Neil to play for Ru'glen, in return for his train fare and a shilling for lunch.

[27] The club opened the ground with a first round Scottish Cup against Albion Rovers, before an attendance of 1,200; the visitors won 6–3.