Daniel Wiffen put in a late surge to retain his 1500m freestyle title in a thrilling final at the European Short Course Championships in Poland.
Team Ireland swimmer Wiffen, who won Olympic gold in the 800m at the Paris Olympics, was second for the majority of the race behind Zalan Sarkany.
However, the 24-year-old put in a stunning final 100 metres to overcome a 1.12 second deficit to the Hungarian.
Wiffen took the lead for the first time with 50 metres to go and won gold by 1.55 seconds over Sarkany, in a time of 14:13.96.
It is a first gold medal for Wiffen, who is from Northern Ireland, since he had surgery on his appendix in August.
It is his second medal of the championships after he finished third behind former Ireland team-mate Jack McMillan in the 200m freestyle final on Tuesday.
McMillan, from Northern Ireland, will race in the men’s 200m freestyle final for Great Britain at 19:27 GMT.
Wiffen’s win secured a second gold medal for Ireland in Poland after John Shortt won the 200m backstroke race on Wednesday.
In the women’s 200m breaststroke, Ireland’s Ellie McCartney booked her place in Friday’s final by winning the first semi-final.
McCartney set the fastest overall time with 2:18.81, just 0.03 seconds ahead of Great Britain’s Angharad Evans, who won the second semi-final.