Debutant loose forward Rob Harley scored a try in stoppage time as Scotland snatched a 17-16 victory over Pacific Nations Cup champions Samoa in Apia on Saturday.
The 22-year-old was put clear from replacement scrumhalf Mike Blair's pass, and flyhalf Greig Laidlaw slotted the conversion to give the visitors the narrow victory, ensuring the Scots return home from their three-match southern hemisphere tour unbeaten.
Andy Robinson's team also upset Australia 9-8 in Newcastle on June 5, then held off a furious late challenge by Fiji in Lautoka last week to win 37-25, with debutant winger Tim Visser scoring two tries.
Scotland, who failed to make it out of their pool at last year's rugby World Cup, had never lost to Samoa in seven previous tests, though they needed a last minute penalty in Aberdeen two years ago to take a 19-16 victory and drew 15-15 at Murrayfield in 1995.
Samoa flyhalf Tusi Pisi scored all of his side's points with a drop goal, two penalties and converted his own try, while Laidlaw added a penalty and also converted Joe Ansbro's first half try.
The visitors had led 7-6 at halftime.