Philip Doyle and Daire Lynch eased to victory in their men's double sculls heat to progress to Tuesday's semi-finals.
On a perfectly still, dull morning at the rowing venue, Vaires-sur-Marne Nautical Stadium, the Irishmen's time of 6:13.24 was the fastest over the three heats and they had almost three seconds to spare from second-placed Spain, taking over from the halfway stage.
"It felt great, it felt really good," Doyle told RTÉ Sport afterwards.
"Obviously that's probably the most nervous race of the whole regatta because you don’t know what everyone’s done in the last few months, you don’t know where they are, you maybe haven’t raced a few of the crews.
"That sorts everyone out, you roll the dice and see where everyone is. It’s nice to come out with one of the faster times."
For Lynch, Spain’s fast start wasn’t anything that concerned them massively.
"We always expect the Spanish to go off very hard. Paul (O’Donovan) and Fintan (McCarthy) train with them over in Banyoles too.
"I don’t think we’re ever too worried about what they’re doing because we were going very quick off the start. We know what times we do in training and if they were going that speed off the start there’s no way they could have kept it up."
They will next race on Tuesday, 30 July.
The women's double sculls crew of Zoe Hyde and Alison Bergin also progressed to Tuesday's semi-finals, finishing third in 6:52.61.
They overhauled Lithuania in the third quarter with France, just ahead of Australia, almost three seconds clear of the Irish.
Bergin said they are used to tough racing in their category.
"We're lucky/unlucky our event is so stacked, it ensures tough racing every single race," she said.
The come-from-behind performance is a bif of a trademark, says Hyde.
"We're known for our second halves, we pulled it off today," she told RTÉ Sport. "We've been training for this for so long. It's amazing to be here and put our performances on the line."
