Simply stunning.

Last-gasp rugby at its breathless best. Edinburgh were almost out on their feet at the end, but they clinched a place in the European Challenge Cup semi-finals with a heroic display of defensive resilience, keeping their line intact in the dying seconds of the game as London Irish mounted a furious final onslaught.

Edinburgh's unlikely hero was Al Dickinson, who had been replaced earlier in the game but who then returned for a second shift when Rory Sutherland went off injured. With the clock already past the 80-minute mark, London Irish prop David Paice crashed through for what would have been the winning try, but Dickinson somehow managed to get his body beneath the ball. French referee Pascal Gauzere studied the video replay from every angle, but he had no possible grounds for ruling that the score was good.

"Dicko did tremendously there," smiled Edinburgh coach Alan Solomons whose side will play Newport Gwent Dragons in the semi-final at BT Murrayfield on Friday, April 17 (7.45pm). "He was absolutely fantastic. In the past, teams would have folded, but we held fast there. I thought that was the big thing and getting a home semi-final at Murrayfield is huge. We showed huge character to get the win.

"It was a tremendous effort from the team. But what a heart-stopping game. I've coached for a long time but I haven't had many like that."

Edinburgh could thank Sam Hidalgo-Clyne just as much. The scrum-half delivered his third man of the match performance on the trot for the club, excellent in every area. His goal-kicking was flawless, but his defensive kicking was probably just as important. How long before he is starting games for Scotland?

In their first experience of European knockout rugby since their giddy run to the Heineken Cup semi-finals in season 2011-12, Edinburgh showed no sign of being overawed by the occasion in the way they started the game. Right from the off, they carried the ball forward with pace and belief, putting the London Irish defenders on the back foot with the boldness of their approach.

They were rewarded after just two minutes when Sam Hidalgo-Clyne landed a long, straight penalty after London Irish skipper George Skivington had been penalised for a high tackle on Tom Heathcote. If the Exiles' fans thought the early setback was something their team would soon shake off, Edinburgh soon disabused them of that idea by keeping up the momentum of their earliest plays. And it was not long before the Scots had more points on the board.

They arrived in the 10th minute after Edinburgh had forced London Irish to concede a lineout in the left corner. Ross Ford found Ben Toolis with his throw, and the lock set up a powerful drive towards the line. The English side took the steam out of the thrust, but they were slow to spot WP Nel nipping out the side door. The prop powered on, rode Blair Cowan's tackle, and crashed over for a try.

Hidalgo-Clyne, who also had a marvellous running battle with his old schoolmate Scott Steele throughout, added the two points. By the end of the first quarter he had also added another two penalties, taking Edinburgh;s lead out to 16-0. It was no more than they deserved, too, for in that opening 20 minutes they had played just about all the rugby.

At that stage, London Irish were facing the possibility of a humiliation, and the prospect seemed to spur them into overdue action. Little by little they began to make the territorial gains that had eluded them earlier, and they finally got a foothold on the scoreboard in the 33rd minute when Shane Geraghty, who kicked erratically throughout, landed a penalty.

Edinburgh would have been happy with a 16-3 lead at the interval, but their advantage was slashed in the last play of the first half when London Irish collected a try. It came when the Exiles released Conor Gilsenan into space down the right touchline and the former Leinster prospect sprinted on to score, but Edinburgh were incensed that the score was allowed as Cowan had appeared to obstruct Ford in the build-up move.

London Irish went on to dominate the third quarter as well, with Geraghty taking another chunk out of Edinburgh's lead with a 45th-minute penalty. They finally got their noses in front in the 53rd minute, when Steele, who clearly relished the moment, followed up a Geraghty chip to score in the left corner for an 18-12 lead for the home side.

The feeling at that point was that London Irish would power on and pull away. However, Edinburgh were not prepared to give up their European hopes without a fight, and they threw on a raft of replacements, worked their way back upfield and went in search of another score of their own.

It arrived right on the hour mark. Edinburgh had built pressure well through the phases, churning and recycling efficiently as they carried play into the 22. Dougie Fife almost went over in the right corner, and as the defence spread back across the pitch Fraser McKenzie spotted his chance and nipped through a gap for a try.

That score nudged Edinburgh back in front. It also added urgency to London Irish, who threw everything into the last few minutes. But Edinburgh threw everything they had back at them. There is no question that their win was richly deserved.

London Irish: A Fenby (T Fowlie, 40); T Ojo, E Griffin, E Sheridan, A Lewington; S Geraghty, S Steele (D Allinson, 70); T Court (M Page, 70), D Paice, H Aulika, (L Halavatau, 51), G Skivington, N Rouse, C Gilsenan (J Sinclair, 60, B Cowan, T Guest.

T: Gilsenan, Steele

C: Geraghty

P: Geraghty (3)

Edinburgh: G Tonks; D Fife, P Burleigh, A Strauss (S Beard, 70), T Visser; T Heathcote (T Brown, 62-67), S Hidalgo-Clyne; A Dickinson (R Sutherland, 66), R Ford (captain; S McInally, 52), WP Nel (J Andress, 70), A Bresler (F McKenzie, 52), B Toolis, R Grant, H Watson, D Denton.

T: Nel, McKenzie

C: Hidalgo-Clyne (2)

P: Hidalgo-Clyne (3)

Referee: P Gauzere (France)