In the individual showjumping qualifying, Ireland's Bertram Allen, Darragh Kenny and Cian O'Connor all jumped clear rounds and are among the 30 riders through to Wednesday's final.
Darragh Kenny was the first Irish rider to enter the arena with VDL Cartello and the Offaly man showed his class to post a perfect clear over a demanding course to take the early lead.
His time of 82.01 seconds saw Kenny finish second overall, meaning he will have an excellent draw as one of the last starters in the final.
Wexford's Bertram Allen then added another excellent clear with the Irish Sport Horse Pacino Amiro with a time of 85.18 leaving them in sixth spot.
Meath's Cian O'Connor with the Irish Sport Horse Kilkenny followed suit, coming home in a time of 88.66 that saw him finish 25th of the 30 qualifiers for Wednesday's final.
Speaking afterwards to RTÉ Sport, the Irish team were pleased with their efforts.
"Cartello jumped super, it felt fantastic and I was really pleased with the round," said Olympic debutant Darragh Kenny.
"We have a very strong team, have a great group of horses. My horse feels in great form and we are very motivated to do damage. I was just seeing how the horse felt, I have never jumped him under lights before but he felt great and I feel very confident.
"There's a bit of shadow and the jumps become a bit brighter; it's spookier. Having an older, experienced horse goes a long way.
Bertram Allen, who partnered Pacino Amiro, and Cian O'Connor on Kilkenny, spoke about the importance of having no faults.
"The main thing was to be clear, the time was only going to come into it if we weren't clear.
"The course is fair but my guy is only nine and is a bit green to this level. It's a lot to take in. He tried his best and hopefully he'll be better for it."
O'Connor added: "You have to jump a clear round now in qualifying with the new format. I have an amazing horse and all the better that he's Irish. Kilkenny really grows in the ring with the lights on, even though there were no crowds here tonight."