The keeper was one of few players to emerge with credit when he made a rare appearance in a 2-0 Carabao Cup defeat at Bristol City on Tuesday.
Grant said: “I'm currently battling it out with England's future number one but that makes it all the more enjoyable. Who doesn't like a challenge?"
He added: “It's been difficult. After a year like last year, which you enjoy so much, it's difficult to then sit on your hands week in, week out which I have been doing for the last five or six weeks.
“The opportunities in the cup are timely and enjoyable for myself. The frustrating thing now is that we haven't got another round to go.
“My focus now will be on maintain my levels and standards and waiting for an opportunity to arise. It was nice for me to show that on Tuesday and remind people that I am ready and able when called upon – but the result was very disappointing."