Defending champions Northampton suffered a shock defeat to Gloucester, while Bath returned to top of the Premiership and Sale beat Leicester.
Six-try Bath powered their way to a bonus-point victory over Sale Sharks to round off the first block of Gallagher Premiership matches in style.
Alex Lozowski booted a penalty with the game's final kick as Saracens claimed a thrilling 37-35 Gallagher Premiership victory over Bristol at Ashton Gate.
Leicester made it three wins from four under Michael Cheika as they beat rivals and defending champions Northampton 24-8 on Saturday.
Bristol moved top of the Gallagher Premiership in bonus-point fashion as they defeated west country rivals Bath 36-26 at the Recreation Ground.
Bath's impressive start to the Gallagher Premiership season continued with a hard-earned 20-15 victory over Leicester in an error-ridden game.
Michael Cheika's reign as Leicester head coach began in dramatic winning fashion as the Tigers claimed a 17-14 Gallagher Premiership victory at Sandy Park.
Rugby league convert Regan Grace has been named to make his union debut for Wales against Queensland Reds.