Surrey 273 (Roy 112, Burns 42, Coles 3-48, Tredwell 3-47 ) beat Kent 233 (Coles 100, T Curran 3-22) by 17 runs (D/L method)

Surrey survived an extraordinary maiden hundred from Matt Coles and a last-wicket stand of 64 - to which Coles' partner Matt Hunn contributed a single run - to progress to the semi-finals of the Royal London Cup. Seemingly bereft of hope, Coles had farmed the strike and swung for the fences to keep Kent alive only to fall for exactly 100 with a famous win almost in sight.

When Kent lost their ninth wicket, Coles was on 42 and 82 were needed from the last ten overs. Hunn only faced five of the next 46 balls, however, as Coles dealt in boundaries, smashing a further six sixes and three fours to fray Surrey nerves. Turning down singles except to keep the strike, Coles faced six consecutive overs before taking a run to reach his century, from 71 deliveries, at the start of the 38th over.

Three balls later, he was out, as a mishit finally went to hand. It was a stunning effort, worthy of the batsman whose hundred he overshadowed: Jason Roy finished on the winning side and he was among the Surrey players quick to offer Coles a consolatory handshake at the end.

"I'm proud of the way I played, but so very disappointed to fall short at the end," Coles said. "In a way, I'd prefer it if we had lost by 40-odd runs, or something, rather than getting that close. It was a full toss that I skied to get out, and I'd also missed out on a few in previous overs, but it is nice to show that I can bat and that, in one-day cricket, nothing is impossible.

"At the start of my innings I just tried to knock it around to get Darren Stevens on strike, and give myself a chance of getting in, and then when he got out I tried to take over that main role while Mitch Claydon and then Matt Hunn hung on with me. I thought the right approach was to keep as much of the strike as I could, and try to hit fours and sixes, and it almost paid off."

Surrey were relieved to have finally mopped up in the third of four Royal London quarter-finals to be affected by rain. A game that was tantalisingly poised at halfway, with Kent mustering an impressive fightback after Roy's hundred, threatened to become one-way traffic as they slipped to 140 for 8 chasing a revised target of 251.

Kent had squeezed into the last eight on net run rate, having been level on points with two other sides, thanks to a washout in the final round but this time the rain did them few favours. A surface that was used in the final Ashes Test had helped put the brakes on Surrey, whose average score in the group stage was a tick under 300. It also made Kent's job in chasing under lights far from straightforward; the clatter of early wickets rendered it practically impossible, at least until Coles dared to dream.

Surrey's attack played their part, of course, with the Curran brothers again to the fore. Sam Curran, who turned 17 less than three months ago, has already made quite an impression for Surrey and the whippy left-armer fatally undermined the Kent innings with an early burst of 3.2-2-6-2 before a shower swept across The Oval, forcing a crowd of around 5000 to go scurrying for cover.

A delay of an hour and 20 minutes ensued, during which a rainbow briefly appeared above the ground. It might be a stretch to liken the Royal London Cup to a pot of gold but, for Kent, a home semi-final would have been worth few shiny sovereigns. Instead, a young, largely homegrown side were handed their second limited-overs quarter-final defeat of the season.

Sam Curran had removed Daniel Bell-Drummond with a terrific ball in his first over and the wicket of Joe Denly, caught at deep square leg hooking the diminutive quick, further stacked the calculations against Kent, as the rest of the players followed him off the field before another ball could be bowled. By the time they returned, the asking rate had been adjusted from less than six an over to more than seven and Surrey's spinners had yet to come on.

Not to be outdone by his little brother, Tom Curran bowled Fabian Cowdrey and Sam Northeast in consecutive overs before Sam Billings, scorer of an incendiary hundred in the group stage as Kent chased down 336 against Notts, was stumped off the bowling of Zafar Ansari. Kent were 49 for 5 after 13 overs and 101 for 7 when Coles, whose previous List A high score was 47, came to the crease.

His pragmatic biffing initially only looked like taking Kent towards respectability and he was dropped on 54, as James Burke stepped close to the boundary rope. Reprieved, he took 13 off an over from Jade Dernbach and 17 off Gareth Batty to make the biggest splash on a watery evening.

Surrey had batted first in every one of their Royal London Cup games this season - and only been beaten once - and duly chose to set the pace after Batty won the toss. Not for the first time, too, they were left to reflect on a scorecard that looked rather top heavy, like a weightlifter teetering on spindly legs. From 192 for 2, a score based around Roy's second hundred in the competition, Surrey lost 8 for 81 from the final 15 overs as they threatened to drop the barbell.

Roy was missed on 39, when Hunn could not hold a sharp return chance in his follow through. Steven Davies was also given a life at slip off the bowling of Coles but Kent's fielders otherwise threw themselves around to good effect.

Roy had driven and pulled crisply, though the only time he managed to clear the ropes was after reaching three figures when latching on to a Fabian Cowdrey full toss. Two overs later he found deep square leg off the returning James Tredwell - who had earlier had Kumar Sangakkara taken at slip off an excellent delivery - and Surrey began a slow spiral towards earth. Tredwell, bowling cannily on a worn surface, provided the tractor beam before Coles and Claydon finally grounded the innings by taking the last five wickets in 27 balls, leaving one unbowled.

High in the OCS Stand, a group of teenagers were playing Cards Against Humanity, which describes itself as "the party game for horrible people". The idea is to lay the funniest card to fill in the blank in an incomplete sentence, eg: "The reason that Surrey threw away such a good start was because ______" or "A preferable alternative to Duckworth-Lewis-Stern would be ______". By the end, at least as far as Surrey were concerned, it felt more like Coles Against Humanity.

Alan Gardner is an assistant editor at ESPNcricinfo. @alanroderick