Bristol Bears pulled off a shock by halting La Rochelle's long winning run with a 13-3 away victory to leave Clermont Auvergne as the only unbeaten side in the European Rugby Challenge Cup.

Top 14 high-fliers La Rochelle beat Bristol 35-22 last weekend to extend their run of consecutive victories to eight matches, but they came unstuck in testing conditions at Stade Marcel-Deflandre on Saturday.

The Premiership side led 6-3 at half-time courtesy of two Callum Sheedy penalties to one from Arthur Retiere, and Bristol captain Jordan Crane slid over for the only try in the mud early in the second half.

Bristol defended superbly under pressure to see out a magnificent win which leaves them only four points behind Pool 4 leaders La Rochelle, who are just one better off than Zebre after the Italian side thrashed Yenisey-STM Krasnoyarsk 58-14.

Clermont are now unbeaten in eight and in control of Pool 1 following a seven-try 49-24 demolition of the Dragons at Stade Marcel-Michelin.

Judicael Cancoriet and Apisai Naqalevu claimed two tries apiece, while Greig Laidlaw scored 14 points with the boot as the Dragons were slayed.

The other Pool 1 clash between Timisoara Saracens and Northampton Saints was called off due to heavy snow in Romania.

Sale Sharks failed to make it four wins out of four in the competition as they were beaten at home by Bordeaux-Begles, Tom Bristow's red card for a swinging forearm proving to be costly as the Top 14 side ran out 17-14 winners, with Florian Dufour scoring a brace of tries.

Harlequins moved to the summit of Pool 5 with a 20-9 success over Benetton Treviso, while Worcester Warriors top Pool 2 after defeating Pau 23-7.