A last-gasp penalty by Ludovic Mercier sent Pau through to the semi-finals of the European Challenge Cup at the expense of Clermont-Auvergne.

Penalties from Stephen Jones and a try from Aurelien Rougerie, Gonzalo Longo-Elvia and Tony Marsh had overhauled Pau’s three-point advantage from the first leg before the former Gloucester outside-half struck four minutes into injury-time.