The fly-half has made 121 appearances for Ireland scoring 1,075 points, both Irish records, with a Grand Slam and four Triple Crowns to his name as well as two Heineken Cups won at Munster.
But the 35-year-old failed to force his way past Sexton into Declan Kidney’s starting XV for this season’s Six Nations and failed to score any points for the first time since the competition began in 2000.
O’Gara described the experience as “torture” but will use it to spur him on to keep fighting Sexton for the No.10 jersey as long as he can.
“I’m not even close to retiring,” O’Gara told the Irish Examiner. “Calls for my retirement … what a joke given my record over the last few years.
“Why should I? Anyone who knows me knows I’ll be the first to call retirement when my time is up.
“And I can assure you my time isn’t up. I plan to play for my country until I’m 38 but definitely until I’m 37. Playing is what it is all about. I love playing for Munster, I love playing for Ireland.
“It was torture not starting in the Six Nations games. You question everything. But then you have to put it to one side – it’s not as if I could have been playing any better at the time – and you have to stay professional.”
After Ireland’s 16-5 Pool C victory over Australia at the World Cup last year, O’Gara suggested he might soon step down from international rugby.
But he now insists retirement is the furthest thing from his mind with a summer tour to New Zealand on the horizon.
“I have never felt better about my rugby,” said O’Gara. “I’ve never worked harder and I am as committed as ever.
“I’m fitter now than I was five years ago and my work rate in training is higher than it ever was.
“I continually question myself. Trust me, I will know when it is time for me to retire from international rugby.
“I’ll be honest with myself and there will come a day when I can no longer produce at this level … that day isn’t even close.”
© Sportsbeat 2012
MORE: The latest football news
MORE: The latest tennis news
BIOGRAPHY: Cesc Fabregas