Two late penalties from Ben Spencer denied London Welsh their first win of the season as Saracens took a giant step towards the knockout stages of the LV= Cup.
The Exiles, who have lost all 13 Aviva Premiership Rugby matches this season, had put themselves in with a shout at the Kassam Stadium after two second-half tries from Opeti Fonua nudged them a point ahead.
But a youthful Sarries side hit back as Spencer, who scored a converted try himself on the stroke of half time before converting Jared Saunders’ score after the break, kept his nerve with two tricky penalties, including one from his own half.
It moves Saracens top of Pool 1 with just one round of group games remaining while London Welsh sit bottom of Pool 4.
Both teams had rung the changes for the clash on Sunday afternoon, with London Welsh including eight members of its Championship winning side in their starting XV.
And it was Justin Burnell’s side who got the chance to apply the early pressure after winning a penalty which Tristan Roberts kicked into Saracens 22.
From the lineout, Welsh pushed for the line but Fonua came up just short and while they won another line out, Saracens quickly regained possession with Romanian international Catalin Fercu eventually cutting through the Welsh defence before failing to gather his chip.
It was proving to be a fast start and the hosts got the first points of the afternoon with Roberts dissecting the posts with a drop goal on 12 minutes.
Saracens nearly replied three minutes later with a try after Spencer’s grubber kick into the corner left them in a promising position but Jack Culverhouse lost possession just metres out.
But the Exiles were not lying down and only a superb try-saving tackle from George Perkins prevented them from going further in front on 22 minutes.
Nick Scott was the architect with a clever break before releasing Alan Awcock but the winger was tackled before being penalised for holding on.
Sarries’ defence continued to hold firm against their opponents as the half wore on, with Exiles failing to make their scrum count.
And the visitors turned the tables just before half-time as Spencer latched onto a hack forward by Max Wilkins following Exiles captain Tom May’s loose pass to run over and score, before adding the conversion himself for a 7-3 lead.
Boosted by the try before the break, it did not take Saracens long to add a second after the restart as Saunders charged through on 43 minutes, with Spencer’s conversion taking their lead out to 14-3.
But Saracens' failure to regather the restart came back to haunt them as Welsh made up ground before Fonua took a short pass from a few metres out before bustling past two Saracens players to cross. Roberts added the extras and the lead was back to four.
Welsh had their tails up and Tongan international Fonua was again to cross the whitewash, barging his way over in the left hand corner. The conversion was missed but Welsh were still in front with 20 minutes left.
They were given a helping hand on 63 minutes too when Sarries replacement back rower Josh Buggea was sinbinned before Exiles replacement Alex Davies – making his first appearance after nine months out with a knee injury – pulled his penalty wide.
Scenting victory, London Welsh continue to put the pressure on but Saracens struck back on 72 minutes as Spencer kept his cool to slot over a difficult penalty to nudge his side back in front.
And he was at it again just five minutes later, taking aim from just inside his own half, to leave Welsh needing a converted try to win, something they ultimately could not manage.
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