Kelleher was between the posts for the Carabao Cup win over MK Dons.
The Irishman told the official Liverpool FC magazine: “Andy was the sub goalie for the game against MK Dons and really helped me that night with his experience, giving me advice and telling me to enjoy it.
“Adrian texted me a couple of days before the game saying 'Good luck' and texted me afterwards saying 'Congratulations'.
“They are both really nice guys and are passing all their experience on, but I also have to look at how well Adrian has done since coming in.
“Considering he had very little time to get used to things here he has done very, very well.
“He'd only been here for a few days when he had to come on and play against Norwich, which is very difficult when you've hardly trained with the team, so he's been really good here."