London Irish have signed former Harlequins lock George Robson from French Top 14 side Oyonnax on a one-year contract.
Rory Clegg has rejoined Glasgow Warriors after five months in France with Oyonnax.
A look back at Saturday's Champions Cup fixtures as Wasps and Toulon booked quarter-final spots.
Team of the week includes strong semi-finalists and leaders of the pack from the Top 14 and Super Rugby.
Ulster are without Ruan Pienaar and Stuart McCloskey for Saturday's vital Champions Cup tie with Oyonnax.
Saracens and Northampton feature among the five European Champions Cup games live on Sky Sports this weekend.
Oyonnax secured the first win in the Champions Cup with a 32-14 victory over four-time European champions Toulouse.
Toulouse travel to Top 14 rivals Oyonnax on Saturday as they look to finish their Pool 1 campaign on a high.
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