Salisbury made the 380-mile round trip from Truro with all three points after a sliding Josh Hedges finish put the Whites into an early lead.
The Whites put themselves ahead in the 8th minute with the first attack of the half, as Robbie Gallagher powerfully carried the ball down the right wing, crossed the ball to Hedgy in the danger area for Hedges to tap home and put the visitors a goal to the good.
There was some defending to do after the early scenes in Cornwall, as Truro looked to get back into the game quickly.
After some resolute defending, Salisbury were on the attack once more via Hedges, who was making his first start this season.
Hedges took on several players in a slaloming run at the top of the box to create an opportunity, but the Tinners' keeper saved it for a corner.
From the subsequent corners, Salisbury arguably had the biggest chance of the game through Bartolo, as the Gibraltian international rattles the crossbar from close distance to deny the Whites their second of the game.
Salisbury went into the break with a deserved lead, but the hard work had just begun for Brian Dutton's side.
The Tinners had the majority of possession and chances coming out of the interval, with a multitude of crosses threatening Will Henry's net, but he stood firm to claim and punch almost every Truro opportunity.
Most notably in the 58th minute, Henry was able to tip a long-range effort over the bar at full-stretch and deny the hosts an equaliser.
After the Whites were successfully riding the storm, Alonge found a rare chance on the counter, holding off his man, cutting onto his left foot and smacking the near post just past the hour mark.
Truro aimed to slaughter Salisbury with death by a thousand crosses coming into the last quarter of an hour, but they were unable to penetrate Will Henry's net.
Confusion ensued in the 88th minute as everyone in the stadium believed the referee had awarded a penalty to Truro after a soft coming together, but it was later deemed a Whites goal-kick.
With three points dropped, looking likely for the hosts, one last cross entered the Salisbury box in the 4th minute of additional time, as Omar Bogle looked to bundle it over the line and leave the travelling Salisbury supporters with their hearts in their mouths; skipper, Sommerton, made sure the ball was cleared in the last kick of the game to ensure Salisbury left with all three points.
Salisbury are now (finally) back at home on Saturday afternoon to face Taunton Town in the second qualifying round of the FA Cup.

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