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.
Northampton returned to the top of the Gallagher Prem table despite a disjointed display in a narrow 28-27 victory over battling bottom side Newcastle.
Noah Caluori scored four tries as Saracens overwhelmed Newcastle 73-14 at StoneX Stadium.
Harlequins defied their abysmal domestic form to stun La Rochelle 27-17 at Stade Marcel Deflandre and secure home advantage in the Champions Cup round of 16.
Northampton Saints were brought back down to earth after they suffered a 50-28 loss away to Champions Cup holders Bordeaux in a repeat of last season's final.