London Irish slipped to a first defeat in 11 matches as Saracens reignited their season with a 16-13 victory.
The Exiles produced a lacklustre performance after their impressive victory over Gloucester last week as Saracens triumphed after a scrappy affair boasting just one try each - both scored in the first half.
The cold, blustery conditions tested the skills of the Premiership's two leading goal kickers to the full. Both Glen Jackson and Peter Hewat missed early penalty opportunities.
After Saracens had dominated the first quarter territorially, Jackson was able to slot from the kicking tee to open the scoring but the Exiles response was immediate.
Sailosi Tagicakibau and Hewat combined and the big Australian full-back strode down the wing before stepping inside and handing flanker Declan Danaher a clear run to the posts. Hewat converted and the league leaders appeared to be off and running.
England prospect Noah Cato, 20, was causing Irish problems and after Tagicakibau allowed the Saracens winger's kick to bounce, the home side induced a penalty which Jackson knocked over to bring up 900 career Premiership points on 24 minutes.
Hewat quickly restored the Irish lead to four points, his side's aggressive midfield defence repelling Saracens, despite the vocal backing of the packed crowd. It was some nifty footwork from Cato and Jackson which at last led to Saracens breaking through the green and white wall just after the half-hour.
Irish scrum-half Paul Hodgson was carried over his own line and, from the resulting scrum and initial ruck, opposite number Moses Rauluni spotted a gap and dived over.
Jackson's conversion put Saracens into a 13-10 lead, which they clung to until the break.
There was to be no repeat of the Exiles' 11 points in the final six minutes of November's reverse fixture in Reading. Hewat missed from the touchline with the Exiles' final attempt to save the game.