Replacement Rob Harley scored a dramatic late try on his international debut to rescue Scotland from a shock defeat to Samoa.
With Scotland trailing 16-10 in the final game of their three-match southern hemisphere tour, incessant pressure finally told on the hosts' defence as Mike Blair sent the Glasgow Warriors flanker through a huge gap by the left-hand post.
Greig Laidlaw slotted the simple conversion to ensure a clean sweep for Andy Robinson's side, following previous wins over Australia and Fiji.
A try from Joe Ansbro, a late addition to the starting line-up after Nick De Luca failed a fitness test on a thigh strain, put Scotland 7-6 ahead at half-time but they trailed after Samoa fly-half Tusi Pisi crossed and converted to complete a 16 point personal haul.
It looked as though Samoa would close the game out, but a solitary lapse in the closing seconds of the 80 minutes let Harley in for the winning score.
The Samoa side were fired up for the game and, after laying down their ritual challenge, the Siva Tau, they followed it up with an equally ferocious opening spell.
They were in complete charge of the opening exchanges, with full-back Faatoina Autagavaia twice coming close to a breakthrough before Tusi Pisi slotted an early drop goal.
It was another four minutes before Scotland made their first serious visit to the Samoan half, but when they did get there they made it pay. Centre Matt Scott made the score with a superb solo break through traffic in the middle of the field, with scrum-half Chris Cusiter in support.
It seemed that Scotland might have blown the chance when they opted to take the ruck ball back towards the Samoan defence, but at the second time of asking they did spread the ball and lock Richie Gray had just enough power to get to the line where Ansbro was on hand to touch down.
Laidlaw slotted the touchline conversion, which proved crucial because Samoa were making a much better job of holding onto the ball and were soon back in kicking range, Pisi cutting the Scots' advantage to one point.
Samoa took first blood in the second half with a second Pisi penalty but Scotland managed to regain the lead with Sean Lamont earning the penalty.
It could not last and the biggest cheer of the afternoon came when Williams provided the cutting edge round the blind side of a ruck and found Pisi in support to score.
When Sean Lamont knocked on a bouncing pass, it appeared Scotland’s chance had gone, but Harley had the final word.
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