The contest was even closer than the scoreline suggests, however, with Grenoble only pulling clear through a converted try from lock Andrew Farley with just four minutes remaining.

Farley's late effort ended the Exiles' stubborn resistance after they threatened a second successive Amlin Challenge Cup away victory.

The sides were tied 6-6 at half time after Clement Darbo and Aled Davies exchanged a brace of penalties and it was the visitors who struck first in the second period as Davies slotted another three pointer after 47 minutes.

But Grenoble seized the initiative just three minutes later when hooker Vincent Campo crossed for the first of their two tries.

Darbo's conversion made it 13-9 yet London Welsh built plenty of momentum and could have retaken the lead had Davies not been off target with penalty attempts in the 62nd and 64th minutes.

London Welsh's hopes of the win that would have given their own quarter-final qualification efforts a huge boost were severely hampered when scrum-half Nick Runciman saw yellow on 76 minutes and Grenoble took advantage of the extra man as Farley powered over moments later.