Kelleher is stepping up with senior goalkeeper Alisson out due to injury.
Slot wrote in today's Liverpool match programme notes: "The one negative from our last game away to Crystal Palace is that we have lost Alisson Becker for the time being.
“No-one needs me to tell them how good a goalkeeper Alisson is or how well he has been performing this season, but I also do not think too many people will need reminding how good a goalkeeper Caoimhin Kelleher is or how well he has performed for us when called upon.
“In an ideal world we would not get any injuries but in any Premier League season it is inevitable that players will get injured so it is vital that we have players like Caoimhin who have the quality and attitude to come into the team and make a positive impact.
“He has done this already this season so hopefully he can do it again.”