Saracens are within touching distance of the Heineken Cup quarter-finals after Owen Farrell kicked them to a superb 37-28 comeback victory over Racing Metro in Nantes.
The England fly-half finished with 32 points as he landed 11 successful kicks from 11 attempts, including ten penalties, in a win full of character and commitment.
The Londoners trailed 19-6 after Racing flew out of the traps with winger Juan Imhoff scoring two fine tries and prop Luc Ducalcon also toucing down inside the first quarter which also saw David Strettle carried from the pitch on a stretcher after being flattened by what appeared a swinging arm from Fabrice Estebanez.
But Saracens held their nerve with Farrell's accuracy from the kicking tee keeping them in touch as the hosts infringed time and again and, allied to a second-half try from full-back Chris Wyles, eventually ground down their opponents to emerge triumphant.
Victory at home over Pool 1 whipping boys Edinburgh next weekend will confirm Saracens' progress to the last eight as group winners.
Yet a Saracens victory looked a distant prospect after they shipped three early tries, Ducalcon got the ball rolling as he rumbled over in the left corner in the seventh minute and, after Farrell had slotted his first penalty, Imhoff extended the lead after he burst on to the ball on halfway and surged away following a fumble from Chris Ashton.
Double for Imhoff
Farrell kept the visitors ticking over, but Imhoff added his second after being sent clear by a well-timed pass from Juan Martin Hernandez - Sebastien converting as he had done for Ducalcon's opener.
Farrell kicked a third penalty but Saracens looked in trouble when Will Fraser was ordered to the sin bin for striking Hernandez in the face with his elbow in a late challenge - Descons kicked the penalty to open a 22-9 lead.
Farrell and Descons traded further penalties before Farrell kicked two more before the break, the second after suffering a shoulder barge that saw second-row Jone Quvo Nailiko binned.
That fuelled Saracens' belief and when Fraser supplied possession from a lineout, Farrell and Tomkins combined to send Wyles flying over before the conversion tied the scores at 25-25 after 48 minutes.
Farrell's seventh penalty handed Saracens the lead for the first time after 53 minutes, although Ashton then put his side under pressure as he was shown a yellow card for striking the Racing centre Estebanez off the ball - Descons kicking the subsequent penalty to level matters again.
Yet Saracens dug in and survived the 10 minute spell with a penalty apiece before their impressive defence pinned back their hosts time and again.
Farrell then added two more penalties including a last-minute strike from distance that crucially denied Racing even the consolation of a losing bonus-point and effectively knocked the French giants out of the cup.
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