Declan Kidney’s side were comfortable winners in the non-Test match, with Ireland set to face Argentina at the Aviva Stadium on Saturday in a vital clash for a second-seed ranking for the 2015 World Cup pool allocation draw.
Heaslip, who was captain for their disappointing 16-12 loss to South Africa, took confidence from their win in Limerick, with the Leinster man praising his team-mates for a clinical performance.
“I was quite proud of the performance of the squad,” said Heaslip. “It was a privilege to lead out a side that was full of such an enthusiastic bunch of guys.
“We talked all week about focusing on our roles and getting the details right. I said during the week that we have been training really well and, against Fiji, we played how we trained.
“We didn’t get any return last week [against South Africa] but I was quite proud to see the return we got this week.”
He added: “I’m more pleased with the zero (conceded) than the amount of tries we scored, to be honest. It is really hard in international rugby, to be able to shut a team out and give them no scores at all. That zero was – I’m more proud of that than the scores.
“It would have been really easy to take the foot off the gas coming into that last quarter but credit to the lads for not doing so. Fiji kept the pressure on and had a good bit of ball near our line but guys stepped up, put their bodies on the line and stepped up at pretty significant times.”