But despite the horror collision with Wallaby skipper Stirling Mortlock, the burly wing will make his comeback ahead of schedule off the bench for Cardiff Blues trip to Leinster tomorrow (Sat).
Roberts, 22, said: ""It's been really frustrating watching on over the festive period and I've been chomping at the bit.
"I believe I'll be fitter and stronger than before but I'm just glad to be back involved and get the chance to try and get some game-time under my belt over the next few weeks."
Roberts, capped seven times by Wales, will be joined on the bench in Dublin by Xavier Rush who ends a four-month injury nightmare.
The All Black star Rush, 31, damaged his knee cap during pre-season training and has completed just 40 minutes this season.
But Blues coach Dai Young insists his talismanic number eight is fighting fit and putting pressure on Wales star Andy Powell.
Young said: "We've done well without Xavier but there is no doubt he has given the squad a massive lift. Xavier has worked really hard on his fitness and no one has been more frustrated with the way the season has gone than him.
"He was a star performer for us last year and it's great to have that selection dilemma between him and Andy."
British Lion Martyn Williams and Ben Blair miss out but should be fit for next weekend's Heineken Cup clash with Gloucester at Kingsholm.
Cardiff Blues: L Halfpenny; T James, J Robinson, T Shanklin, G Thomas; N Robinson, J Spice; J Yapp, R Thomas, T Filise, B Davies, P Tito (capt), M Molitika, A Powell, R Sowden-Taylor.
Replacements: G Jenkins, G Williams, S Morgan, X Rush, R Rees, C Sweeney, J Roberts.