His country's record goalscorer drew level with Shay Given on 125 international caps after appearing from the bench on Sunday, and celebrated by adding two late goals
The Boys in Green saw opposition goalkeeper Georgi Loria sent off in the first half for a foul on striker Shane Long, and went 2-0 up at the Aviva Stadium after goals from Richard Keogh and Simon Cox either side of half-time.
Keane came on at the interval and scored his 55th international goal with a tap-in from Conor Sammon’s cross, and then his 56th late in the match with a neat finish after teammate Jeff Hendrick took advantage of a poor pass out of defence to set him up inside the box.
After the match the 32-year-old reflected on his achievements with surprise, and told reporters: "If you had said to me 10 years ago I would get that many, I would have said you were crazy."
Keane made his national team debut at 17 years old in 1998 and became the side’s record goalscorer in 2004, scoring four goals as the Green Army reached the knockout stages of World Cup 2002.
The LA Galaxy striker added: I'll look back in years to come, but for now I'm looking forward and hopefully I'll get a few more. It is always nice to score goals, for a striker it is very important for your confidence."
Manager Giovanni Trapattoni also paid tribute to the record-breaking striker, and commented: "It is a beautiful moment for him. Robbie was destined. He started to play as an 18-year-old and was one of the youngest creative players in Ireland."