Harlequins produced a stunning upset as they reached the Champions Cup semi-finals by beating French heavyweights Bordeaux-Begles 42-41.
Harlequins produced a 47-19 win over Ulster that keeps them in the chase for home advantage in the Champions Cup knockouts, and leaves Ulster out.
Clinical Ulster secured a big victory against Racing 92 in the Champions Cup while Bath edged out Cardiff and holders La Rochelle lost again.
Tommy Freeman scored two tries as Northampton opened their Champions Cup campaign with a three-try 28-19 victory away to Glasgow.
La Rochelle broke Ulster hearts in the very final play to book a last-16 spot, while Ospreys, Saracens, Sharks and Bulls won too.
Leinster cruised to a dominant victory over a depleted Gloucester in the Heineken Champions Cup, while Sharks narrowly beat Bordeaux to continue their strong start...
Harlequins fell to defeat at South African side Sharks in their opening Heineken Champions Cup game as Leinster and Gloucester started with victories.
Bristol Bears secured a narrow Champions Cup Round of 16 first leg win at Sale Sharks, while La Rochelle won well at Bordeaux-Begles.