Anasta agreed to a two-year deal with the Tigers earlier this year but insists he's very much focused on leaving the Roosters on a positive note by winning the remaining four games.
However, he revealed it's been difficult not to think about his six-year stint with the club coming to an end.
"To be honest, it's been dawning on me all year," Anasta said.
"It wasn't an easy decision and it wasn't something I thought would happen, so it's been tough mentally because of that.
"I've been ready for a while now and it's coming to an end. It will probably kick in more the last couple of weeks, but I am looking forward to the future and a new beginning."
The Roosters win over St George Illawarra last Friday almost certainly ensured they will avoid the wooden spoon.
A win over Parramatta on Saturday will guarantee it, and edge the Eels closer to a last-place finish, but Anasta is wary of the desperation of Brad Arthur's side, who have found some form in recent games.
"Watching Parramatta play against the Tigers it was 22-6 in the first half after 20 minutes so it shows how dangerous they can be," he said.
