The race for the Premiership's last play-off space is hotting up and Harlequins put down their marker by beating Leicester Tigers.
Exeter Chiefs and Saracens kept winning at the top on Saturday, while Leicester Tigers' Premiership status is not yet secured.
Newcastle Falcons are running out of time to save themselves from Premiership relegation after losing at home to Leicester Tigers.
Tom Youngs will miss three of Leicester Tigers' final four Premiership matches after being banned for a dangerous challenge on Ollie Atkins.
Exeter Chiefs earned a home semi-final with four games to spare, while Saracens scored a late try to hurt Newcastle's survival hopes.
Ben Youngs had an operation on his shoulder and will consequently miss the rest of Leicester Tigers' Premiership campaign.
David Denton has not recovered from the concussion he suffered back in October and will play no further part in the season.
Leicester Tigers had no response after Northampton Saints raced clear in the first half of Friday's Premiership grudge match.
Leicester Tigers have confirmed England centre Manu Tuilagi has signed a new deal with the Premiership club.
Saracens suffered a second defeat in three at Bath, while Sale Sharks piled on the agony for Leicester Tigers.
An injury to Shambeckler Vui and suspension for Tolu Latu has forced the Waratahs to bring in Tatafu Polota-Nau as short-term cover.
Saracens eased past Northampton Saints but table-topping Exeter Chiefs had to repel a second-half rally from Sale Sharks.
Mathew Tait, who made his England debut at the age of 18, has called time on his career on medical advice.
Worcester Warriors eased their relegation fears with a third victory of the season over Leicester Tigers, who have lost five in a row.
Leicester Tigers limped to defeat at Saracens, meaning the victors once again sit top of the Premiership.
Saracens and Racing 92 secured home quarter-finals in the Champions Cup but the hopes of Exeter Chiefs are over after defeat at Munster.