Beeslack scored three goals in each half to condemn their Division 4 rivals to defeat.
The balance of play was, however, by no means reflected in the sides' relative fortunes in front of goal. In addition, despite the eight goals scored, the goalkeepers at either end – Billy Taylor for Beeslack and Gerry McBride as Lochend No.1 – displayed no little prowess between the sticks.
Lochend showed more initiative in going forward in the early stages of the game, Jack Roden hitting the crossbar with a cross-cum-shot after beating Beeslack's Ben Carstairs on the right.
On ten minutes, Thistle's first forward foray of the match saw them assume an early advantage. Gary Watson picked up possession 20 yards out and, with the Lochend defence standing off him, found the bottom left-hand corner of the net.
Five minutes later, Beeslack doubled their lead when Lee Murray's long free-kick from halfway ran to Mark Hall, who had ghosted in unnoticed from the left. McBride saved superbly from Hall's snap shot but Thistle captain Craig Sinclair swept the rebound into the net.
Roden again asserted himself as Lochend's most potent threat in attack by beating Carstairs on the right and cutting inside before showing good technique in unleashing a 15-yard strike that shot just wide of the top right-hand corner.
For all their foraging up front, though, Lochend couldn't craft a goal and went three behind on 22 minutes. When the ball fell to Beeslack's Hall after a cross from the right, he clinically lashed it into the net from ten yards.
Goodall forced a good save from Lochend keeper McBride early in the second half but the goalkeeper was unable to keep hold of the ball, spilling to Kieran Burt, who netted the rebound to make it four.
Beeslack forward Hall found himself in the clear with the chance to add a fifth on 51 minutes but fired narrowly wide. He did, however, atone for that miss two minutes later by netting from close range after his pace had taken him clear of the Lochend defence.
Roden mercifully pulled a goal back for the reds on 55 minutes. Jake Knowles' free-kick swung dangerous towards goal from the halfway line and, with goalkeeper Taylor beaten, the ball crashed back off the crossbar, straight into the path of Roden, who converted despite the best efforts of Taylor to claw the rebound effort away.
Hall's sheer speed once more confounded the Lochend backline four minutes later, though, and the margin was restored to five as the striker buried another close-range effort behind McBride.
The final goal of the game came when Lochend defender Connor Merrilees bravely strode out of defence in possession of the ball and curled a sumptuous ball through the Beeslack backline and into the forward-running furrow of team mate Roden. The No.16 took the ball without breaking his stride and advanced before expertly slotting the ball past Taylor to register a second consolation strike for Lochend.
Beeslack coach Billy Taylor was surprised at the nature of his side's cup win. He said: "I wasn't expecting a win of that magnitude but I was quietly confident. Most of the games between us this season have been very close. Our passing play up front was phenomenal."
Beeslack Thistle: Billy Taylor, Liam Logan, Ben Carstairs, Dean McCafferty, Lee Murray, Calum Steel, Craig Sinclair, Gary Watson, Lewis Bowie, Euan Goodall, Jack Kidd, Mark Hall, Chris Murray, Rhys Galloway, Kieran Burt, Fraser Amos
Lochend: Gerry McBride, Ryan McMurdo, Daniel Brennan, Darren Gallaghan, Jake Summers, Jay Lothian, Ryan Sanderson, David Jack, Ryan Henderson, Sam Campbell, Jake Chalmers, Jacob Reid, Jack Roden, Jake Knowles, Ryan Philip, Connor Merrilees, Liam Fisher.