Dallaglio, who has been the subject of the intense media spotlight throught the RBS Six Nations is determined to put in a good performance this weekend.
"I have always got a point to prove and I am probably at my most dangerous when I have got a point to prove," he told BBC Radio Five Live. "Sunday is an opportunity for me to play on a big stage. I haven't had that much at international level this season and I haven't had too many games at Twickenham this year so I quite fancy starting one.
"Playing club rugby is all about big days out at finals and the opportunity to win trophies. It is something we have been fortunate enough to do in the last three years and if we can add another one to that on Sunday that would be great.
"But we have got a worthy adversary in the Scarlets. They represent a lot of the players I didn't get the chance to play against in the RBS Six Nations."