Juan Imhoff’s try five minutes from time after Finn Russell had broken free of his shackles eliminated Saracens, the defiant holders, who found the loss of their captain, Brad Barritt, just after the hour one blow too many. Until the centre left the field after two players fell on him, Sarries had been in control and were six points ahead.
Without him, a team already without 10 players who started the season at the club, as well as the suspended Owen Farrell, had to reshuffle a back division that had contained Russell and the France centre Virimi Vakatawa, who combined to create Imhoff’s match-winning try.
It was a moment of skill to decide the tightest of contests. The first half was dominated by defence. Racing looked to widen their point of attack, minimise the threat of Maro Itoje and stretch Saracens, but they made little ground and resorted to the boot.
Saracens were not fed the diet of penalties they enjoyed in beating Leinster in their Dublin quarter-final, although that changed after the restart when they brought Billy Vunipola into the game, and had little meaningful possession to exploit after Alex Goode looped around his midfield and freed Sean Maitland, who had crossed from his wing to the right after an early lineout.
Neither tryline was threatened as each side waited for the other to blink first. Racing lost their flanker Fabian Sanconnie in the third-minute after he tackled Goode and his head made contact with the fly-half’s elbow before striking a knee on the way to the ground.
Saracens also had to make an early change, when the Scotland centre Duncan Taylor injured his left shoulder. He was replaced by Dominic Morris, a 23-year-old academy graduate with fewer than a dozen league and European starts for the club, who helped swing the match towards the holders in the third quarter with thunderous tackles.
Racing took the lead after 10 minutes when Teddy Iribaren kicked the first of his three penalties after Tim Swinson failed to roll away from a ruck. The scrum-half was then wide with many effort from inside his own half before Saracens, after a passing interchange between the Vunipola brothers, equalised through Goode who gave his side the lead with a 29th-minute penalty after the hosts bungled an interception.
Two Iribaren penalties gave Racing a 9-6 interval lead but Saracens started the second period strongly, raising the pace of the game and getting on top in the scrum. Antoine Claassen avoided a yellow card for a deliberate knock-on before Georges-Henri Colombe followed up a knock-on with a scrum offence to give Goode the chance to restore Saracens’ lead.
Colombe was immediately hauled off but his replacement, Ali Oz, was penalised at his first scrum for Goode to kick his fifth penalty. Saracens had two opportunities to put Racing a long way back. Morris was hauled down 15 yards from the line after breaking tackles, but was penalised for holding on, and when Racing lost possession in their opponents’ 22 and Barritt hacked on, Alex Lewington had to stoop low to pick up the ball with the line 20 metres in front of him and lost his balance.
When Barritt went off dazed after Donnacha Ryan and Michael Rhodes landed on him, the depleted ranks finally told on Saracens and they had not been able to use their bench as the hosts did. Maxine Machenaud kicked a penalty before, with five minutes to go, Finn Russell applied the coup de grâce.
The Scotland fly-half foiled the rush defence by chipping into space for Vakatawa, who had been contained by Barritt, to run on to and feed Russell who drew what remained of the defence to send Imhoff away.
Racing were home and Saracens were out, not to return for at least two years.