O’Brien, who has been in and out of the Newcastle side, had come under pressure from the performances of Richard Dunne at Manchester City, but a clean sheet and the only goal of the game went a long way towards sealing his place for Israel next month.
Kerr said: “He has had to wait a long time to get his chance because of the form of the likes of Steve Staunton, Gary Breen and Kenny Cunningham.
“But he has come in and done well and it shows how important he is to us because in the last nine matches in which he has played we have conceded just one goal.
“But you have to be able to defend well to win games. That is the basis on which all teams compete.”