Clermont gave themselves the chance of qualifying for the quarter-finals of the Heineken Cup with a 24-14 victory over Saracens on Friday.
The French outfit finished second in Pool 2 on 19 points and could now reach the last eight if results over the weekend go their way.
Wesley Fofana, Willie Wepener and Tasesa Lavea took them to a 19-14 lead inside the final 10 minutes before replacement Ti'i Paulo was bundled over two minutes from time to give them was may be a vital bonus point.
David Strettle scored Sarries' only try before the break while Owen Farrell added three penalties, but with nothing to play for the Londoners were undone by the extra desire of their opponents.
The Top 14 side swept into the lead after just three minutes when Kevin Senio and Lavea combined to tear a hole in the home defence, Fofana darting through to score by the posts with Anthony Floch adding the extras.
It took the hosts nearly 20 minutes to make an impact, but a sustained attack comprising seven phases was ultimately halted by an offside offence, and fly-half Farrell kicked the resulting penalty.
That lifted the crowd and Clermont found themselves on the back foot for the first time, as Farrell added a second from 40 metres to bring his side within a point.
And within four minutes Saracens had raced into the lead. Hooker Schalk Brits did the damage with a strong break before timing a fine pass to England wing Strettle, who had raced in off his right wing and carved through the remaining cover.
Farrell's conversion attempt rebounded off a post but the hosts led 11-7 if only for three minutes, as the visitors responded with vigour.
Kini Murimurivalu broke through midfield and passed to Floch. The full-back was grounded feet from the line by Chris Wyles, but managed to pop up a pass for hooker Wepener to score, and although Floch's attempted conversion went wide they led by a point at the break.
The second half began with Saracens taking the game to the French, whose tackling was up to the test when their line was threatened.
Saracens had an opportunity to regain the lead on 49 minutes, but Farrell's penalty attempt from out on the left missed the target, and another effort on 52 minutes was even further awry, much to the delight of the visiting French support.
However, Saracens pressure was finally rewarded on 54 minutes when the young stand-off kept his nerve from 35 metres and drilled a penalty straight between the posts.
Then it was the turn of the home side to produce the big hits as Clermont raised their game following a raft of replacements.
They regained control on 64 minutes when a succession of drives on the Saracens line ended with fly-half Lavea crashing between the posts for a try which he also converted.
Clermont had to soak up some pressure despite surging breaks by Noah Cato and Kelly Brown, and they sealed what could be a crucial extra point when Paulo was driven over after being awarded a five-metre scrum.
Pens: Farrell 3
Tries: Fofana, Lavea, Paulo, Wepener
Cons: Floch, Radosavljevic
Saracens: 15 Chris Wyles, 14 David Strettle, 13 Brad Barritt, 12 Nils Mordt, 11 Noah Cato, 10 Owen Farrell, 9 Neil de Kock, 8 Ernst Joubert, 7 Justin Melck, 6 Kelly Brown, 5 Mouritz Botha, 4 Hayden Smith, 3 Carlos Nieto, 2 Schalk Brits, 1 Rhys Gill.
Replacements: 16 Jamie George, 17 Jared Saunders, 18 Petrus du Plessis, 19 Jacques Burger, 20 Andy Saull, 21 Richard Wigglesworth, 22 Luke Baldwin, 23 James Short.
Clermont: 15 Anthony Floch, 14 Brent Russell, 13 Marius Joubert, 12 Wesley Fofana, 11 Kini Murimurivalu, 10 Tasesa Lavea, 9 Kevin Senio, 8 Elvis Vermeulen, 7 Alexandre Audebert, 6 Julien Bardy, 5 Jason White, 4 Loic Jacquet, 3 Vincent Debaty, 2 Willie Wepener, 1 Lionel Faure.
Replacements: 16 Ti'i Paulo, 17 Thomas Domingo, 18 Clément Ric, 19 Thibaut Privat, 20 Alexandre Lapandry, 21 Ludovic Radoslavjevic, 22 Aurélien Rougerie, 23 Jean-Marcel Buttin.
Referee: Alan Lewis (Ireland)