Flood missed the opening game of the competition against Italy at Twickenham with a calf injury. He made his return when he came off the bench against Wales at the Millennium Stadium two weeks ago.
Now he has been handed the No10 jersey by England team manager Martin Johnson, replacing former Tigers stand-off Andy Goode for the game at Croke Park.
Flood will win his 24th England cap, 11 of which have been in the starting XV, with four at fly-half. And he aims to make the most of it by cementing a place in Johnson’s long-term plans.
Flood said: “It was frustrating not to be involved against Italy because of my calf and I was happy to come off the bench against Wales.
“Hopefully I can set a platform to put people into space and cause problems for the opposition.
“It's the time you want to be to putting your hand up and making a mark, to cement a position in the squad in which there is a huge amount of competition."
Flood is Tigers’ leading points scorer this season and he believes his game has benefited from his summer move to Leicester from Newcastle Falcons.
“Being in the Leicester environment is a tough one. You have to mature quickly and there is not really much room for a mistake,” said Flood.
“Leicester play in a lot of high-profile games. I have enjoyed my time there and being in that environment at the club has allowed me to improve my game.”
The 23-year-old will link up at half-back with Tigers teammate Harry Ellis, something Flood is looking forward to.
He said: “It's always good to play alongside Harry Ellis. He brings a lot of enthusiasm and he has the ability to turn the game.”
Ellis is in line to win his 25th England cap after starting the first two games of this season’s Six Nations.
He said: “I’ve played with Toby many times - for the majority of this season at Leicester. He’s a great communicator and runs the show well.”
He added: “The criticism we got before the Wales game only gave us added motivation.
“Against Wales we didn't get much ball, we had to do a lot of defending. We were bitterly disappointed at not getting a victory but we did perform better than we had against Italy. We’re going in the right direction; there are some areas we need to improve on but there were a lot more positive things to take from the game.
“We want to keep building and improving and not take a step backwards. We're all very eager to keep improving and get wins for England - hopefully that will happen this weekend.”
Tigers teammates Julian White and Tom Croft have been named on the bench for the trip to Dublin while hooker George Chuter will travel with the England squad as cover for Northampton’s Dylan Hartley, who has been recovering from a calf problem.