Kelleher made 67 appearances for Liverpool but had to content himself with being the understudy to the Reds’ Brazil keeper Alisson.
His transfer to Brentford saw him join a mini Irish contingent that includes international team-mate Nathan Collins, with former Republic of Ireland player and coach Keith Andrews now managing the Bees.
Kelleher has achieved his aim of becoming first-choice keeper at a club, and is delighted with how things have started in west London.
“I feel a lot more comfortable and confident getting that weekly game time,” said the Cork man.
“It’s a good change for me and hopefully it pays dividends for the national team as well. It’s been a positive change for me. I’m getting more confidence and gaining experience every week.”
He is hoping to bring that club form into Saturday’s opening World Cup qualifier against Hungary at the Aviva Stadium on Saturday (19:45 BST).
After a difficult start to manager Heimir Hallgrimsson’s tenure, things have slowly begun to turn, with a pair of victories against Bulgaria ensuring they retained their place in Nations League B.
The next objective is to push on and target World Cup qualification with Kelleher hopeful they can open their Group F campaign in perfect style on Saturday.
“That’s certainly the target for us,” said Kelleher, who identified former Liverpool team-mate Dominik Szoboszlai as one of Hungary’s main threats.
“It would be ideal to start off with a victory against one of our bigger rivals in the group. A draw isn’t the end of the world, but the next step for us is to qualify for a major tournament, so we need to start off with a win.”
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