An opening strike inside the first 20 seconds, followed by a second goal early on in the second half was sufficient to cancel out Spartans' solitary effort, an equalising penalty on the half hour.
Whatever the whisperings within the Windsor players' huddle prior to kick-off, there must have been uttered some words of Churchillian inspiration, as the East Lothian underdogs emerged in the opening seconds with fire in their bellies and, seemingly, a job to be done.
It took less than ten seconds for Windsor to earn a corner kick on the left and just a few moments more for Scott Dargo's inswinger to be converted at the far post by the head of Ross Cowan.
Despite their efforts in an opening period that they dominated, Windsor were unfortunate to a degree in the concession of an equalising goal 30 minutes later. Regardless of their lack of luck, the arm of one Musselburgh defender certainly made contact with a high-speed ball at a corner kick and a subsequent penalty award elicited little complaint from the Windsor players. This presented Spartans striker Scott Hunter with the chance to level from the spot, and he duly dispatched the penalty low into the right-hand corner.
Spartans played the better football in broaching their opponents' final third territory, but were forced to adopt a "shoot on sight" policy, often from a range of 30 yards from goal – a result of both the resistance of the Windsor defence and, perhaps, a lack of invention on the part of the North Edinburgh side.
Windsor managed to delve far deeper into the opposition penalty area shortly after half-time and capitalised on a lucky break to reassume the lead. A shot at the Spartans goal was deflected directly into the path of Steven Harper who, in the clear ten yards out with just goalkeeper Murray Jackson to beat, sidefooted the ball clinically low into the net.
Chasing the game in the final 20 minutes, Spartans undoubtedly enjoyed more possession but still failed to seriously trouble Windsor goalkeeper Andrew McQueen, whose defence of Dargo, Cowan, Arran Ponton and Michael Lynch could be relied upon to divert any impending danger.
A lovely sweeping Spartans manoeuvre, switching the ball from one side of the box to the other with mesmerising speed via Sean Wringe and Steven McGinn, teed up David Stewart on the left 12 yards from goal, but Stewart delayed his shot and allowed a desperate Windsor defence to block his strike, claiming handball in his frustration and with little foundation.
Hunter's clever one-two with Wringe opened up space for a low drive on goal but Windsor goalie McQueen was equal to the Spartans boy's effort. Wringe himself produced a snapshot on the volley from a right-wing cross but couldn't keep the ball down and watched it fly over the crossbar.
Harry Wright had a glorious chance to ensure a more comfortable closing stage for Windsor but, after skipping two challenges while skirting the bye-line to the right of the Spartans goal, the Musselburgh substitute cut inside to create an angle to shoot from and, instead of squaring to the later-incandescent Antony Marziban, pushed his shot well off target as he lost his balance.
The narrow victory, though, was sufficient for Windsor and their coach James Carlyle. He said: "I expected a hard game because Spartans are a cracking side. The last time we played them at Pinkie they really dominated us and won 3-1.
"In this game, though, we were more dangerous going forward but, in the last 20 minutes, we were really under the cosh. It really was a team effort. We've had a decent season, having been to five semi-finals, and this is our first bit of silverware."
Spartans Reds: Murray Jackson, Liam Riordon, Alex Brown, Patrick Lewis, Lewis Kidd, David Stewart, Steven McGinn, Stuart Patton, Scott Hunter, Liam Donnelly, Sean Wringe, Matthew Cunningham, Connor Armstrong, Gianpiero Franchi, James Hymers, Greig Patterson.
Musselburgh Windsor: Andrew McQueen, Scott Dargo, Arran Ponton, Ross Cowan, James Carlyle, Michael Lynch, George Gibson, Steven Harper, Laurie Jones, Michael Slater, Peter Johnstone, Scott Wright, Lewis Russell, Lewis Knight, Jamie Duffner, Antony Marziban.