Saracens moved to within two points of the Premiership summit by beating Newcastle Falcons, after struggling Worcester Warriors had earned a historic win in a low-scoring affair at leaders Exeter Chiefs.
The Warriors defeated the defending champions 6-5 to record a first win at Sandy Park, putting a 12-point buffer between themselves and bottom club London Irish.
A fine defensive effort kept the Chiefs at bay during a first half in which two Chris Pennell penalties had put Worcester into a 6-0 half-time lead.
Mitch Lees crossed for Exeter after the break to ensure a nervy ending, but the Warriors held on for a famous win.
Massive thanks to the Warriors faithful today who drove the boys on, especially at the end!-- Worcester Warriors (@WorcsWarriors) February 10, 2018
It's days like these that make some of those long trips worth it! pic.twitter.com/8FWqFIhcDX
That allowed Saracens to close on top spot thanks to a convincing 25-3 win over Newcastle at Allianz Park.
Sarries had 20 points at the break, thanks to Richard Barrington scoring, a penalty try and the handy boot of Ben Spencer, while a late score from replacement Max Malins rounded off the victory.
Leicester Tigers' hit-and-miss season continued in a 24-17 reverse at Gloucester, with Henry Trinder scoring twice for the hosts.
Rounding off the action, Irish lost for the 13th time in 14 league matches this season as Sale Sharks ground out a 13-9 victory.