The Irish men's and women's 4x100m freestyle relay teams both set new national record, while Conor Ferguson set a personal best time as he reached the final of the 50m backstroke at the LEN European Aquatics Championships in Budapest, Hungary.
The women's quartet of Mona McSharry, Danielle Hill, Victoria Catterson and Erin Riordan finished fifth in their relay heat in a time of swam 3:44.37, lowering the record set in 2009 by almost three seconds.
In the men’s event, Jack McMillan, Jordan Sloan, Shane Ryan and Max McCusker came home in 3:16.88secs, bettering the time that was set by McMillan, Sloan, Ryan and Robbie Powell at the 2019 World Championships.
Neither relay team has advanced to tonight’s final, but both have advanced their chances of qualifying for Olympics.
In the individual events, Ferguson reached the final of the 50m backstroke but Darragh Greene missed out on a place in the final of the 100m breaststroke.
Ferguson touched the wall in a personal best time of 24.81 in his semi-final to qualify for Tuesday's final.
Longford swimmer Greene started in lane eight of Monday's second breaststroke semi-final but the Irish record holder in the event - one of two events in which he has earned the Olympic consideration time - but finished eighth in a time of 1:00.26 in a heat won by Great Britain's Rio 2016 gold medal winner Adam Peaty.