Gloucester recorded a 29-24 bonus-point victory over Northampton, while there were also English Premiership wins for Exeter, Harlequins, Bath, Leicester and Saracens.
Having suffered a humiliating 57-10 loss to Sale in round five, coach Johan Ackermann’s side had a point to prove against the Saints, who were on a four-game winning streak.
Northampton looked set to take a 7-5 lead into the break, but a try by outside centre Henry Trinder in stoppage time put the hosts 10-7 up.
The Saints regained the ascendancy two minutes into the second half via a converted try, but Gloucester scored three times in succession to open up a handy 15-point advantage.
Northampton added 10 points to their tally, but it was only enough to bag them a losing bonus point.
In other matches, the Newcastle Falcons were brought down to earth with a 34-24 defeat to the Exeter Chiefs, young flyhalf Marcus Smith kicked 17 points for Harlequins in their 42-16 thumping of the Sale Sharks, and Bath lashed the Worcester Warriors 29-12.
The Leicester Tigers toppled London Irish 28-27, and Saracens brushed aside Wasps to clinch a 38-19 win, with hooker Jamie George scoring a hat-trick.
Round 6 results:
Gloucester 29 Northampton Saints 24
Exeter Chiefs 34 Newcastle Falcons 24
Harlequins 42 Sale Sharks 16
Bath 29 Worcester Warriors 12
London Irish 27 Leicester Tigers 28
Saracens 38 Wasps 19