Bordeaux-Begles, hammered 50-24 in their backyard by Sale Sharks a week earlier, scored a surprise first win of the campaign when they came from behind at AJ Bell Stadium to throw Pool 3 wide open.
A try by Luke James which was converted by Rob du Preez (pictured) suggested it would be another Sale win but it was 7-7 at the break when Florian Dufour crossed and Baptiste Serin converted.
A red card for Sale's Tom Bristow proved costly and a second try from Dufour pushed the French in front.
Serin converted and landed a penalty to lead 17-7 and while Rob Webber hit back with a converted try, the French held on for a surprise win.
The result leaves Pool 3 a battle between Sale Sharks and Connacht, with the English side coming to the Sportsground in the next round leading the pool with 16 points, with Andy Friend's men three points back.
Connacht will conclude the pool away to Bordeaux-Begles with Sale Sharks at home to Perpignan in the final round.
All would seem to hinge on the clash at the Sportsground in the next round on Saturday, January 12 in what promises to be an intriguing encounter.