Sri Lanka legend Kumar Sangakarra has underlined why he was voted the greatest one-day player of all-time in a cricket.com.au fan poll, with a nerveless century to steer Surry into the semi-finals of England's domestic one-day competition.
Sangakarra finished unbeaten on 130 having smashed the final ball to the boundary to seal the win in a 29-run stand with No.11 Jade Dernbach.
Surrey stuttered with a late-order collapse as they lost 4-16 between the 44th and 48th overs, and 12 were needed from the final over.
With four balls remaining, Sangakkara leapt across his stumps to paddle sweep Mohammad Azharullah into the sightscreen over the wicketkeeper's head for six.
It was an extraordinary shot at such a tense moment.
With two to get from the final ball, the 38-year-old Sangakkara carved a boundary wide of point.
It left Northamptonshire heartbroken after a fine comeback in the field and Ben Duckett ruing his dropped catch off Sangakkara on seven.
That chance aside, the Hobart Hurricane's crowd favourite was composed and classy, working the bowling around and taking very few risks.
He reached a third one-day century for Surrey in 116 balls – it was his 37th career ton in 50-over cricket.
Earlier, Northants had been bowled out for 276 with an over to spare. Josh Cobb gave them a steady start having lost the toss but regular wickets fell throughout the innings and the hosts were in danger of posting a total well below par without Rory Kleinveldt's fine late-order effort.
Kleinveldt's 76 in 62 balls gave the Northants innings a late revival from 9-227.
Cobb and Wakely had earlier moved the Northants innings along after Dernbach claimed two early wickets as Richard Levi flicked into the hands of James Burke at deep square-leg and Ben Duckett slapped to cover diving forward.
In the night's other quarter-final, Jason Gillespie's Yorkshire were boosted by a host of England stars returning to the county as they held on for an 11-run win against Kent.
Ex-England opener Adam Lyth blasted his way to 88 from 96 balls, while Joe Root added 45. Gary Ballance had hit 37 before he was brilliantly run out by Kent 'keeper Sam Billings.
And Adelaide Strikers import Adil Rashid showed his all-round skills to blast a quick-fire 24 as the home side reached 9-256.
Yorkshire's Liam Plunkett then grabbed four wickets – including a spectacular caught-and-bowled dismissal of Darren Stevens who had looked serene on his way to a half-century.
Perth Scorchers import David Willey added three wickets as Kent were bowled out in the 48th over, 12 short of the target.
Yorkshire and Surrey will now face each other in the one-day cup semi-finals on August 28, while Warwickshire and Somerset face off in the second semi the following day. The final will be played at Lord's on September 17.