"It's difficult to compare to how I was before, and I know there are some things I need to improve, but I can feel myself getting better and better with every game," Agger told the club's official website.
"Maybe I am not there yet, but I will be soon.
"Of course sometimes it's difficult but you have to keep working hard to improve yourself and that's what I am trying to do.
"It has been difficult with the injury last year but that's the past. Hopefully I'll be back to 100 per cent soon.
"Outside of the pitch I'm really happy. I am enjoying everything. The people in Liverpool are so friendly. I was really surprised when I came to the city how friendly the people were compared to other places I have been. I cannot complain about anything. I feel at home."