There are some daunting venues in Europe but none more formidable this season than this atmospheric and character-laden old stadium. Factor in temperatures nudging 30C, and the prospect of Harlequins enjoying a vintage quarter-final weekend in Bordeaux were supposedly on a par with a local sommelier returning from the cellar with a bottle of Chateau Twickenham.

So much for that theory, with Quins now able to toast the club’s first Champions Cup semi-final as reward for clinching one of the all-time great knockout contests. Rugby union does not come much more gloriously watchable, with a lion-hearted forward effort and two tries from Will Porter edging out a home side who racked up 100 points in two games against Saracens here this year.

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Bordeaux did not have the brilliant Damian Penaud or Matthieu Jalibert, both sidelined by injury, but, equally, Quins were lacking Danny Care, Joe Marler and Joe Launchbury, who withdrew just prior to the game with a calf strain. It mattered not as Alex Dombrandt, Chandler Cunningham-South, Will Evans and Fin Baxter, the latter performing heroically in the scrums opposite the mountainous Ben Tameifuna, showed why Quins’ future is increasingly bright.

It amounted to the most staggering entertainment, with Quins’ pack proving the unexpected stars of a spectacular 12-try show. That said, there was drama and intrigue until the very last with Maxime Lucu lining up a very kickable conversion to clinch potential victory. To the horror of a packed home crowd, however, the French international scrum-half’s angled kick sailed wide and Quins will meet either Toulouse or Exeter in the last four.

Leinster emphatically ended La Rochelle's bid for a hat-trick of Champions Cup titles by beating them 40-13 at the Aviva Stadium.
Ronan O'Gara's team defeated Leinster in the last two finals by a combined margin of just four points.
But La Rochelle's quest for silverware ended at the quarter-final stage this time around as Leinster marched on in pursuit of a record-equalling fifth tournament triumph.
Wing James Lowe (2), scrum-half Jamison Gibson-Park, flanker Ryan Baird and hooker Dan Sheehan scored tries, while fly-half Ross Byrne kicked three conversions and three penalties as Leinster never looked in danger of suffering another loss to their fierce rivals.
La Rochelle saw prop Louis Penverne go over for a try on the stroke of half-time, with Antoine Hastoy adding two penalties and a conversion.
But they were blown away during the second period, failing to score a point, as Leinster stormed into yet another Champions Cup semi-final.
Byrne opened the scoring with an eighth-minute penalty from 45 metres, and Leinster dominated the early exchanges, which was underlined when they scored their opening try just nine minutes later.
The La Rochelle defence was stretched in all directions before Lowe touched down and Byrne converted, before Byrne and Hastoy kicked penalties and a second Hastoy three-pointer made it 13-6.
Another Byrne strike restored a 10-point lead before Leinster struck again following clever interplay between Lowe and Gibson-Park that ended with the scrum-half sprinting over unopposed.
Byrne's conversion left Leinster in charge of the contest, but they were unable to close out the opening 40 minutes before their opponents dragged themselves back into contention.
Leinster infringed inside their 22 and La Rochelle's powerful driving lineout game was graphically illustrated when Penverne touched down and Hastoy converted to make it 23-13 at the break.
But La Rochelle were dealt a double blow early in the second period, conceding another try and seeing scrum-half Tawera Kerr-Barlow carried off.
Baird was the beneficiary of a poor attempted tackle from Hastoy - and Byrne converted after a lengthy delay while Kerr-Barlow received treatment before leaving the field.
La Rochelle knew they had to score next or there was no way back, but they conceded two tries in four minutes.
Sheehan claimed the first following flanker Josh van der Flier's powerful surge, then Lowe added his second when he finished impressively after chasing a kick into space. PA Media

Only the memorable Munster v Wasps semi-final in 2004 runs this see-sawing epic anywhere close as the most exhilarating latter-stage game the tournament has known. The visitors’ preferred plan was clear from the outset: run Bordeaux and their big forwards around for as long as possible. As early as the third minute, after an initial surge from Cunningham-South, André Esterhuizen found space down the blindside and Porter, lurking on his inside, cantered over unopposed.

It was only the start. A hard-running Oscar Beard stretched a complacent home defence and just as a hitch-kicking Marcus Smith was about to put an unmarked Tyrone Green over on the right, a deliberate knockdown by Matéo Garcia conceded a yellow card and a fully justified penalty try. The hosts were 14-0 down and urgently needed to wake up.

They duly did so, Lucu diving over in the left corner and the decision being allowed to stand despite Porter having been taken out just behind the ruck. Suddenly it was a completely different jeu and all the decisions were going the way of Bordeaux, with Romain Buros being credited with a close-range try the Italian referee had initially declined to give.

Quins needed to conjure something special to wrest back momentum and, bang on cue, it arrived. The visitors launched a daring raid from the own 22 and Cadan Murley cleverly twisted away from a couple of tacklers before finding Dombrandt in support. The No 8 stood firm in the tackle long enough to throw a world-class offload to Porter who rounded off a spectacular move by regathering his own chip ahead for a classic score.

By half-time the lead was 28-12, with Evans burrowing over after a purposeful lineout drive and Smith drilling over another conversion. Quins, though, have a long history of blowing hot and cold and the signs were distinctly ominous when Bordeaux’s French international centre Nicolas Depoortère scooped a Lucu offload off his toes and scored in the left corner four minutes after the restart.

But once again Quins’s scrum rode to the rescue, another penalty getting their maul rumbling again to send Dombrandt over. One missed tackle on Buros, though, was all it took to set up Louis Bielle-Biarrey for Bordeaux’s fourth try and, in the blink of an eye, the home side were ahead for the first time thanks to a try from replacement Madosh Tambwe with 15 minutes remaining.

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The last act, though, was to prove even more compelling. Sam Riley lost the ball as he was about to score from another rolling maul before another sweeping Quins move saw Louis Lynagh put Green over to seize the lead again.

Could they cling on? Tambwe scored again with four minutes left but Lucu’s near miss allowed Quins to celebrate unquestionably their finest victory on French soil.