England international suffers 'gruesome' injury on 4G pitch

*This article contains some graphic images*

The Wasps scrum-half was playing against Lyon in Saturday's Challenge Cup semi-final.

Wasps hopes of a first European final in 15 years were ended by a narrow 20-18 defeat despite Robson crossing for the only try of the opening 40.

​But the result left more than a sting for Robson, who wrote on Twitter 'On a positive note, that was the last 4G we play on this season'.

Wasps were ultimately undone by knock-ons and errors as their hopes of silverware ended in frustration.

Here are some of the worst rugby injuries:

This was the shocking souvenir Brian O'Driscoll was left with when he collided head-on with Scott Williams during the 2014 Ireland v Wales Six Nations’ match in Dublin.

The South African tighthead prop did not blame Sarries flanker Maro Itoje - whose studs were responsible- for the sickening injury.

Warburton has also been the victim of huge blows to the face, with this one against Leinster a particular shiner. The flanker was taken off after just 13 minutes at the Arms Park and required stitches.

The Wales hooker's modelling career came to a sad end in February when this happened to him during a match for Gloucester. On Twitter, he accused his opponent of trying to steal his nose!

The Bath flanker resumed his career despite suffering permanent eye damage in an October 2010 collision with Gloucester’s Charlie Sharples.