Pool winners Sale, Harlequins and Exeter are joined by best-placed runners-up Saracens in the Premiership Cup semi-finals.
Lock David Ribbans signs a new deal with Northampton Saints, extending his stay at Franklin's Gardens until 2022.
Wasps and Harlequins earn last-gasp victories at Northampton and London Irish respectively in the Premiership Rugby Cup.
Manu Vunipola - the younger cousin of England's Mako and Billy - scores his first Saracens try as the Premiership Cup begins.
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