Edinburgh staged a second-half comeback to pick up a hard-fought 26-24 win over Gloucester in the Champions Cup and consigned the visitors to a fifth straight defeat.
Bath lost a 26-point lead in an epic south-west derby only to snatch back victory in the most dramatic fashion in the closing seconds to beat Exeter 33-26, before Northampton Saints returned to the top of the Prem table.
Northampton stunned the Prem Rugby champions Bath with a devastating display of running rugby featuring a hat-trick of tries by freewheeling England back Tommy Freeman.
An astonishing start which saw Bath 28-0 ahead inside 19 minutes proved crucial as the Prem side saw off Munster 40-14 in their Champions Cup opener.
Bath snatched a 36-29 victory over Saracens that propelled them two points clear at top of the Gallagher Prem.
Leicester Tigers eked out a 36-35 win against Sale Sharks as Bath, Harlequins and Exeter all won by big scorelines in Saturday's Gallagher Prem action.
Billy Searle's penalty with the final kick of the game secured Leicester a dramatic 22-20 victory over Gallagher Prem champions Bath.
Playing rugby has no causal link to motor neurone disease, according to an expert in the incurable muscle-wasting condition.