Casey could be presented with a chance to start against Japan on Saturday as head coach Andy Farrell assesses his options with games against Australia and South Africa to come.
The 26-year-old is hoping to make a greater impact on the remaining autumn internationals if he features after admitting he was disappointed with his display against New Zealand and his part in opposite number Cam Roigard scoring their fourth try.
“I wasn’t too happy, you want to come on and impact games. I probably had very few touches, and I felt I didn’t come on and light it up like I wanted to,” he explained.
“[Roigard’s try] it’s completely on me. I got caught up at the time, I’ve watched it 25 times and I still don’t know what I was thinking at the time, but I take it on the chin.
“It’s never nice when a scrum-half scores against you.”
Casey believes he has “grown” a lot over the last two years but acknowledges he still has a lot to work on to be “consistently world class”.
“The scanning and the calmness, when things click in your mind and you’ve seen things you’ve never seen before, that’s the biggest area of growth for me.
“To continue improving, I need to be an all-round player and bring my full game to every game.
“I’m very happy with where my basics are. so it’s probably adding layers onto that.”
