All four Pro14 sides in European Rugby Champions Cup action on Saturday secured victories, three coming against French opposition.
Bath finished the game with 11 men as they suffered defeat to lowly Worcester Warriors in the 98th minute.
Bristol Bears ended 2018 with a huge win over Newcastle Falcons, while Bath moved up to fifth with victory over Leicester Tigers.
Saracens had not suffered defeat since April, but they were soundly beaten by Exeter Chiefs to lose top spot in the Premiership.
Leicester Tigers have put their faith in Geordan Murphy to arrest their alarming slide after a run of eight consecutive defeats.
Back-to-back wins over Newcastle Falcons have Edinburgh closing in on a quarter-final place in the European Champions Cup.
Premiership leaders Saracens made it three wins from three in the European Champions Cup after victory over Cardiff Blues on Sunday.
Defending champions Saracens have won each of their opening nine Premiership fixtures as they stayed perfect by beating Wasps 29-6.
Leicester Tigers almost took advantage of Saracens' ill-disciplined display, but fell short in a Premiership cracker at Welford Road.
Gloucester had Danny Cipriani back from a ban and the fly-half was instrumental in their bonus-point 36-13 win over Leicester Tigers.
Freddie Burns apologised after costing Bath a Champions Cup win over Toulouse with a botched try five minutes from time.
Saracens are level with Exeter at the top of the Premiership after fighting back to beat Harlequins.
Sale Sharks had to settle for a losing bonus point despite scoring three tries against Leicester Tigers at Welford Road.
Leicester Tigers produced a storming second-half fightback but Ted Hill's late try gave Worcester Warriors a first win of the season.
The Ricoh Arena played host to a Premiership classic on Sunday as Wasps overcame 14-man Leicester Tigers 41-35 in an eight-try thriller.
Danny Cipriani inspired Gloucester's comeback as a former Bath player denied the hosts victory at the Rec on Saturday.