Surrey held their nerve at drizzly, floodlit Lord's to beat Middlesex by five wickets with four balls to spare in a rain-shortened match and grab the last place on offer in the Royal London Cup quarter-finals. Surrey, last year's beaten finalists, will now face Northamptonshire in the last eight, at Northampton.

Ben Foakes and Zafar Ansari, the fifth-wicket pair, were Surrey's batting heroes as they put on 66 in 8.5 overs to chase down Middlesex's 101 for 8 in what became a 16 overs per side contest after coming together at 35 for 4.

Foakes eventually chipped the fourth ball of the 15th over to mid-on, with the scores level and after scoring 45 from 33 balls with two sixes and four fours, leaving Ansari to hit the winning run from the second ball of the final over by pulling Toby Roland-Jones for his first four to finish 29 not out from 28 balls.

For Middlesex, who would have earned a quarter-final themselves if they had won, it was a desperately disappointing night. If the match had been declared a no-result - which for most of a dank day seemed the likely outcome - Middlesex would have qualified instead of Surrey.

Kent's win at Sussex and Hampshire's narrow loss to Somerset, the South Group winners, meant that both sides knew well before the end of the match that, if they won, they would take the final quarter-final place available.

Surrey, though, went hard from ball one even with an initial asking rate of just above six runs an over, and losing four key wickets in the first six overs of their chase put them under self-inflicted pressure.

Jason Roy, driving expansively at the first ball of the innings, edged Roland-Jones to the keeper and, in the second over, Steven Davies flashed James Harris to slip where Ollie Rayner leapt to his left to hold a fine catch.

Rory Burns dragged a ball from Harris into his stumps on 5 and then, after smashing three sixes - two in an over from Roland-Jones, to midwicket and straight, and the other over long-off against Harris - Aaron Finch was bowled for 24 by offspinner Rayner, whose celebrations underlined how important a moment Middlesex thought it was. Sadly for them, however, the superb Foakes-Ansari partnership then took the game away.

Play finally got under way at 6.30pm, after a frustrating afternoon of heavy showers and abortive attempts to mop up by the Lord's groundstaff. Much of Middlesex's innings, too, was played in light drizzle, with both teams determined to stay out in the middle and get a match played.

A frenzied opening to the game saw Paul Stirling power Jade Dernbach through the covers for four and flat-bat a ball from Tom Curran over midwicket for six. Nick Gubbins, too, pulled Sam Curran sweetly for six but, before the third over was done, Middlesex were wobbling at 23 for 3.

Dawid Malan went for a first ball duck, caught behind flashing at Dernbach, the left-handed Gubbins was spectacularly caught one-handed by keeper Foakes, diving to his left, when on 7 he edged a drive at Tom Curran, who then foxed Stirling with a slower offcutter to defeat his push-drive and bowl him for 13.

George Bailey pulled Dernbach for six but was then bowled for 12 by Gareth Batty's arm ball as he advanced to the offspinner, and James Franklin's 13 ended with a lofted catch to long on off Tom Curran. John Simpson played a responsible hand, with 29 from 28 balls, but then edged behind as he tried to angle to third man a ball pushed across him by Stuart Meaker.

Driven off by heavier drizzle at 86 for 6, after 12.4 overs, Middlesex limped to their final total of 101 for 8 after a 20-minute interruption, with Roland-Jones and Rayner caught attempting big hits and the match length reduced again to 16 overs per side because of the further time lost.