Ireland's acting captain paid tribute to Ireland's travelling support on a night to remember.
At half-time in Ireland's crunch Pool D encounter with France,
they led 9-6 and had just lost their captain and star out-half.
Ireland had enjoyed the better of the opening exchanges but would be trying to turn over the French at a World Cup for the first time without some pivotal personnel.
Joe Schmidt revealed that the Irish dressing room was shorn of Johnny Sexton [groin] and Paul O'Connell [hamstring] as they were off receiving medical treatment. Heaslip, who took over as captain, provided a further insight.
He said, "At half-time, it was quite a calm changing room.
"Everyone just switched into their roles and problem-solved. We adapted what we had and came up with solutions - who was fitting in where and how we were going to proceed.
"There was a lot of work [to be done] and Joe has already touched on the work that Ian Madigan got through. All the guys - Iain Henderson, Chris Henry and all the subs - came on and got through a massive amount of work.
"That's what we always say - fit in first, then add value to the game. That's exactly what they did. We were focused and that's exactly what you have to be against France because they are that type of side who will punish you if you're not [focused]."
The subs certainly fit in as
Ireland closed the game out to win 24-9 and set up a quarter final with Argentina.
Heaslip also heaped praise on the Irish supporters, who must have numbered north of 65,000 in Cardiff today.
https://twitter.com/SportsJOEdotie/status/653280254497320960
The 31-year-old will be hoping Ireland can get as many injured troops back onto the pitch, next week, as Argentina will pose another huge physical test.
Heaslip may go into battle in a back row comprising of himself, Chris Henry and Jordi Murphy. Peter O'Mahony has twisted his knee and Sean O'Brien should be getting a call from the citing committee.
Who covers them on the bench - with Donnacha Ryan a back-up second or back row - is anyone's guess.
