The three-time Olympian just missed out on bronze at the 2016 Rio Games - setting the current Irish record of 47.97 seconds
Waterford sprinter Thomas Barr has announced his retirement from competitive athletics.
Barr made history when he won bronze in the men's 400 metre hurdles at the 2018 European Championships.
He was the first Irish male sprinter to win an outdoor European medal in the 84-year history of the event.
The three-time Olympian just missed out on bronze at the 2016 Rio Games - setting the current Irish record of 47.97 seconds.

Man City Complete Domestic Double With FA Cup Triumph
Ireland Captain McCabe Linked With Chelsea Switch
Fonseca Marches Into French Open Quarter-Finals
Kildare's Walsh Scores Career-Best Finish On LPGA Classic
Monday Morning Sports Update
Kildare Duo Shine As Leinster Cruise Into URC Semi-Finals
PSG Retain Champions League After Shoot-Out Drama
Munster's URC Campaign Ends In Pretoria