Leicester Tigers head coach Michael Cheika will leave at the end of the season after deciding not to extend his contract with the club.
Saracens missed out on the chance to book a Champions Cup round of 16 home tie as Castres produced a stunning victory in London.
England, British and Irish Lions and Leicester Tigers back Anthony Watson has been forced to retire from rugby on medical grounds.
Tom Willis surged over for two tries as Saracens dispatched second-placed Bristol Bears in a 35-26 victory in the Gallagher Premiership on Saturday.
Bath inflicted a record Gallagher Premiership defeat on 14-man Saracens as they powered to a 68-10 victory at the Recreation Ground.
Bristol sent out a major title statement as Pat Lam's men set a new Premiership record in a thumping 54-24 win over Leicester at Welford Road.
A round-up of Sunday's Investec Champions Cup action, where both Ulster and Leicester Tigers suffered defeats to French opposition.
Defending champions Northampton suffered a shock defeat to Gloucester, while Bath returned to top of the Premiership and Sale beat Leicester.