Bath secured home advantage in the Gallagher Prem play-offs after beating Leicester 24-22 at a rainswept Recreation Ground.
England international Ellie Kildunne will leave Harlequins at the end of the season.
Alex Hearle scored a hat-trick as Newcastle staged an incredible second-half comeback to secure a 45-42 triumph over Sale at Kingston Park.
Fin Smith's last-second penalty snatched a breathless 41-38 victory for Prem Rugby leaders Northampton Saints against second-placed Bath at Franklin's Gardens.
A last-minute try by England fly-half Fin Smith saw Northampton Saints snatch a thrilling 35-28 victory over Exeter Chiefs at Sandy Park on Saturday afternoon.
Former England lock Joe Launchbury will retire at the end of the season.
Sale hooker Nathan Jibulu has received a six-week ban for biting Harlequins prop Will Hobson.
Bristol's Gallagher Prem play-off hopes were dealt a major blow after they suffered an 18-14 defeat against struggling Harlequins at the Principality Stadium.