For much of the 90 minutes it looked like Chelsea were going to edge it then and there. Diego Moreira got things going when he gave us the lead with a fine finish into the bottom corner.

Although Brighton levelled in fortunate circumstances after a long kick from the keeper went all the way through, Dujuan Richards won and converted a penalty - albeit at the second attempt - to give us a deserved half-time lead. After weathering a brief spell of Brighton pressure relatively comfortably, we extended our lead with a lovely goal by Richards, curling his second of the game into the bottom corner from distance.

It looked like that would be that, but then the Seagulls pulled one back on the counter and went on to equalise in a goalmouth scramble following a corner, sending the tie to extra time. It was a similar story in the added 30 minutes, as Jimmy-Jay Morgan turned in Harrison McMahon's low cross from close range to give us the lead, but then Brighton levelled for the third time in the game from a set-piece.

Things were finally decided with just two minutes remaining on the clock, though, with a brilliant end to an incredible match when Zain Silcott-Duberry chipped the keeper from a long way out to settle things for good for the 10 men of Chelsea, and keep our chances of claiming the Premier League 2 trophy alive.

Brighton started strongly in the opening minutes and applied some pressure at the start, with one header looping narrowly wide of Max Merrick’s left-hand post, before Kaiden Wilson produced a strong block when former Chelsea Academy striker Louis Flower threatened to get a sight of goal in the box.

Taking charge

It was Chelsea who came closest to opening the scoring on the 15-minute mark, though. A good move down the left, which started with Tyrique George applying pressure high up the pitch, ended with Kiano Dyer being fouled wide of the Brighton box. Dylan Williams whipped in the free-kick and Leo Castledine glanced a header across goal, but it bounced just wide of the far post.

Good pressure from George nearly paid off again shortly afterwards, pressing on the edge of the area before Richards arrived to smash the loose ball goalwards. His snapshot was on target but central and the keeper was able to palm it over the bar.

We were starting to put our opponents under pressure now, with George and Richards looking particularly dangerous on the break. It paid off after 20 minutes. Jimi Tauriainen went down in pain after a heavy challenge, but Chelsea saw the opportunity to break and took it.

Richards charged forward before George took over and found Moreira in space on the edge of the box. He stood up his defender well before jinking inside onto his right foot and drilling a low shot which was past the keeper and in the bottom corner before he saw it.

The opening goal came at a cost, though, as Tauriainen was unable to continue, being replaced by McMahon. The Seagulls tried to hit back, but first Wilson and then Williams made excellent interventions in the box before we regained a measure of control.

Level but not for long

The problems we were causing were summed up when Moreira pressured the Brighton keeper into a short kick straight to George, although the shot stopper got back on his line just in time to save his ambitious effort. Unfortunately, Brighton then levelled straight from the resulting kick upfield, with a mix-up at the back by Chelsea allowing Benicio Baker-Boaitey to nick in and round Merrick before slotting into the empty net.

We went straight back on the attack, though, dominating the ball in the period before half-time. McMahon forced an excellent save from Tom McGill with a powerful effort from range, but we did soon retake the lead from the penalty spot.

Richards produced a lovely turn on the edge of the box to make a chance out of nothing and when he was pulled down by Ruairi McConville the ref pointed to the spot. Richards took it himself and although McGill produced another great save to keep out his initial effort, the Jamaican forward was able to slot in the rebound.

We ended the first half putting Brighton under more pressure, but had to be content with just the one-goal advantage at the break.

In contrast, we were the ones who had a bit of defending to do early in the second-half, but were equal to the Seagulls' initial pressure. It was perhaps inevitable that the visitors would attempt to make an impact early in the second half, as they came out trailing by a single goal.

It wasn't long before we stamped our authority back on the game, though. There was a warning when our front three of Moreira, Richards and George combined well to allow the latter to curl narrowly wide, but with an hour played we did extend our lead.

Richards did well not to give up on the move when at first the chance seemed to have gone, but his finish was of the very highest quality. There was only one thing in his mind as soon as the striker picked up the ball, and he promptly opened up his body to curl into the bottom corner from 20 yards, giving the keeper no chance.

There was no question which side was on top at that point and we were close to a fourth when a lovely flowing team move down the right ended with George flicking Moreira's cross towards the near post, but it didn't have the power to beat the keeper from a tight angle.

No way clear

However, Brighton then pulled one back on the counter to set up a tense finish to the match. It came from a strong run down the left by Kamari Doyle, which allowed Luca Barrington to find Joshua Duffus to head in from six yards.

It still looked as though Chelsea had done enough to book our place in the quarter-finals, but that didn't prove to be the case. A Brighton corner was floated in from the right and following a block dropped into a scramble. It eventually broke the visitors' way and Leigh Kavanagh was able to equalise from close range.

More of the same in extra time

Things then went from bad to worse, as an injury to Leo Castledine meant we finished the match with 10 men and Brighton had two good opportunities from set-pieces late on, but it remained 3-3 at the end of 90 minutes, meaning we were heading to extra time.

The Blues were finally able to bring on Richard Olise to replace Castledine and restore a full compliment of players at the beginning of the additional 30 minutes. It was a scrappy start to extra time without much rhythm and the best early chances fell Brighton's way in transition, Brody Peart dragging his shot wide and then Merrick saving well at his near post.

We applied good pressure at the end of the first half of extra time, though, and it paid off with a goal. There was patient build-up from the Blues and when Williams' cross was half-cleared, McMahon did well to recycle possession, drive into the box and cross low for Morgan to turn in.

Somehow, even that still wasn't enough to secure the win, as two minutes later we failed to fully clear a corner ourselves, allowing Duffus to level the scores for Brighton yet again.

The decisive moment arrives

The was another setback for Chelsea when we came back out for the final 15 minutes of extra time without Michael Golding, who became the third Blues player forced off after being caught in the head by a wild high boot from the goalkeeper, which somehow went unpunished by the referee. With all five substitutes used, that meant we would play the rest of the game reduced to 10 players.

With less than three minutes remaining out of 120, the match was finally decided in Chelsea's favour. In an incredible conclusion to an unbelievable match, Dyer played an early pass forward to Zain Silcott-Duberry on the right and the winger did well to spot the keeper had slipped while attempting to backpedal. Silcott-Duberry steadied himself and lofted a brilliant finish over the keeper and into the net from a long way out.

What a way to win it right at the end, but it is Chelsea who progress to the quarter-finals of the Premier League play-offs.

What is next

Chelsea will now travel away to Arsenal, who defeated Manchester United 6-2 tonight, in the quarter-finals of the Premier League 2 play-offs, with that match to be played over the weekend of 10-13 May.

The teams

Chelsea (3-4-1-2): Max Merrick; Kaiden Wilson, Harrison Murray-Campbell, Dylan Williams; Leo Castledine (Richard Olise f-t), Jimi Tauriainen (Harrison McMahon 24), Kiano Dyer, Zak Sturge (c) (Zain Silcott-Duberry 81); Tyrique George (Michael Golding 81); Dujuan Richards, Diego Moreira (Jimmy-Jay Morgan 73)
Scorers: Moreira 22, Richards pen 41, 61, Morgan 105+2, Silcott-Duberry 117
Booked: Sturge 47, Wilson 119

Brighton (4-2-3-1): Tom McGill; Ben Jackson (Casper Nilsson 61), Leigh Kavanagh, Ruairi McConville, Jacob Slater; Kamari Doyle (Zane Albarus 83), Samy Chouchane; Luca Barrington, Caylan Vickers, Benicio Baker-Boaitey (Joshua Duffus 61); Louis Flower (Brody Peart 73)
Unused sub: Steven Hall
Scorers: Baker-Boaitey 34, Duffus 72, Kavanagh 85, Duffus 105+4
Booked: Jackson 26, McConville 40