London Irish battled to claim a draw at Bristol Bears despite seeing Ollie Hoskins sent off on the stroke of half-time.
Exeter Chiefs were in control at half-time, but Bristol Bears scored 20 points without reply in the second half to snatch a stunning win.
Taqele Naiyaravoro impressed again as Northampton maintained their winning start to the Premiership season on Friday.
Northampton Saints and Gloucester followed up narrow away wins on the opening weekend by easing to home successes in the Premiership.
Nathan Hughes made a big impact on his Premiership debut for Bristol Bears, while Luke Morahan claimed a brace in an emphatic derby win.
Bristol Bears have changed Pat Lam's title to director of rugby after he signed a new deal at Ashton Gate.
Northampton Saints took the final Premiership play-off spot despite losing to Exeter, while Bath secured Champions Cup rugby next term.
The race for the Premiership's last play-off space is hotting up and Harlequins put down their marker by beating Leicester Tigers.
Exeter Chiefs and Saracens kept winning at the top on Saturday, while Leicester Tigers' Premiership status is not yet secured.
Worcester Warriors and Bristol Bears eased their relegation fears, leaving Newcastle Falcons needing a great escape to avoid the drop.