Saracens suffered their first defeat of the season as they went down to Bath in the English Premiership.
Alister Hargreaves return to first team action didn't go as planned as tries in each half by centres Jonathan Joseph and Kyle Eastmond helped Bath to their first victory over Saracens since 2010.
Coming just two weeks after their 45-0 dismantling of Leicester, the win was another statement of intent against last season's beaten finalists.
Northampton Saints capitalised on Saracen's loss by claiming a hard-fought 19-12 victory over London Irish to move to the top of the log.
In other results, Greig Laidlaw kicked 18 points as Gloucester eased past Leicester, Newcastle picked up their first win of the season against the Exeter Chiefs, London Welsh remained winless as they went down 52-0 to Harlequins, while Danny Cipriani produced another strong display to inspire Sale to a 25-14 victory over Wasps.
Round 5 results
Baths 21 Saracens 11
Gloucester 33 Leicester Tigers 16
London Irish 12 Northampton Saints 19
Harlequins 52 London Welsh 0
Newcastle Falcons 29 Exeter Chiefs 24
Sales Sharks 25 Wasps 14
Photo: Michael Steele/Getty Images