Folkestone will play Merstham in the Ryman League Division 1 South play-off final on Saturday after edging past Whyteleafe in the semi-finals on Tuesday night.

An own goal by Leafe captain Jason Thompson, three minutes into extra-time, eventually settled the tie after it had finished 1-1 at 90 minutes.

Roscoe D'Sane had cancelled out Ian Draycott's opener to keep Whyteleafe's promotion hopes alive but Thompson then put through his own goal before missing a penalty at the other end.

On a dry, dusty pitch at the Fullicks Stadium, the game took a while to ignite.

Draycott drove a shot over the bar when his strike partner Richard Atkins failed to control a cross, before a poor kick by goalkeeper Tim Roberts almost cost Folkestone.

Jason Henry latched onto the loose ball and played in D'Sane but the former Woking, Aldershot and Torquay striker lost his composure and lashed his shot wastefully wide.

Whyteleafe's Sam Clayton then failed to hit the target with a tame shot which rather summed up the first quarter of the game.

However, the visitors began to assert themselves on a nervy-looking Folkestone.

Henry's cross-shot drifted wide and when D'Sane chased a long ball over the top, it required a brilliant saving tackle from Invicta skipper Liam Friend to stop him opening the scoring.

Leafe should have taken the lead from their next chance. Roberts pulled off a good save to keep out Ryan Fowler's powerful effort before D'Sane, with the goal gaping, contrived to miss from a couple of yards out.

The home side were guilty of over-playing at times but they took the lead against the run of play on 42 minutes.

Ronnie Dolan's shot deflected behind and from the corner which followed, Draycott rose well to head home his 43rd goal of the season from close-range.

However, that lead was wiped out nine minutes after half-time.

Frankie Chappell failed to cut out a straight ball and D'Sane pounced, running clear and coolly rolling the ball beyond Roberts' right hand to make it 1-1.

The goal seemed to spark Folkestone into life as they embarked on their best passage of play.

A fine team move totalling 15-20 passes had manager Neil Cugley applauding in the technical area even though it finished with a wayward shot from Atkins.

Dolan and Atkins combined to set up Jordan Wright for a shot which was blocked and when Nat Blanks played the ball into Wright's feet, Draycott blazed the ball high over the bar.

Whyteleafe were fading and Micheal Everitt went close with a dipping volley after a long throw had dropped at his feet.

Wright almost lobbed Leafe goalkeeper Sheikh Ceesay late on but then came a big chance for the visitors.

Substitute Greg Andrews got in down the right and cut the ball back for Henry, who should have scored. But his shot lacked power and Folkestone cleared the danger before the whistle blew to signal extra-time.

Jon Pilbeam, on from the bench, was denied by a brilliant Ceesay save when play restarted, the goalkeeper dropping low to his left after Pilbeam had worked a yard of space in the box.

But there was nothing Ceesay could do to stop Folkestone taking the lead just a minute later. Wright met Matt Newman's left-wing cross with a fantastic cushioned volley and Thompson's attempted clearance ended up in the back of the net.

Barely had Folkestone retaken the lead, however, when it looked as though they'd be pegged back for a second time.

Osa Obamwonyi's dangerous cross from the left had the home side in trouble and when Nat Blanks shoved Henry inside the six-yard box, referee Paul Howard pointed to the spot.

Up stepped Thompson but his penalty kick was so far off target it sailed into the neighbouring cricket club.

The home crowd roared with laughter - and then heaved a collective sigh of relief.

Folkestone should have put the tie to bed in the second period of extra-time.

Wright sent a speculative effort over the bar after Everitt had picked out Pilbeam with a wonderful crossfield pass. Then substitute Ashley Miller swirled a left-wing free-kick towards the top corner and the slightest touch from Ceesay carried the ball onto the inside of the far post. Many supporters couldn't believe the ball had stayed out - but somehow it had.

Chappell headed a free-kick straight into Ceesay's gloves before Pilbeam spurned a great counter-attacking opportunity, holding onto the ball when he could have squared for the unmarked Miller.

Whyteleafe pumped late balls into the box but Friend and his fellow defenders stood firm to send Folkestone through to their third play-off final in six seasons.

Folkestone: Roberts, Vincent, Chappell, Friend, Blanks, Dolan (Pilbeam 80mins), Everitt, Newman, Wright, Atkins (Miller 100mins), Draycott. Subs not used: Wraight, Austin, Fender.

Whyteleafe: Ceesay, Hamlin, Bird, Patterson-Bohner, Obamwonyi, Thompson (Pratt 113mins), Fowler, Grant, D'Sane (Andrews 87mins), Clayton, Henry. Subs not used: Graham, Smith, Penfold.

Attendance: 788.