Ahead of the world swimming championships in Kazan, Russia, from August 2-9, here are five European names to look out for in the pool at the Kazan Arena Stadium:
KATINKA HOSSZU (HUN) -- The Hungarian Individual Medley queen has gone from strength to strength since winning both the 200m and 400m world titles in Barcelona two years ago and remains the name to beat in Kazan in the combined strokes.
The 'Iron Queen' posted the fastest time of the year with 2mins 08.66sec in Charlotte, USA, and won last season's six-meet USA Swimming Pro Series by beating a host of Americans on their own doorstep.
In the final meet in Santa Clara last month, she won both the 200m IM and claimed victory in the 200m backstroke, in which reigning world and Olympic champion Missy Franklin finished third.
It remains to be seen whether Hosszu will bid to win multi-events in Kazan or just focus on defending her IM titles with China's Olympic champion in both 200m and 400m IM Ye Shiwen looking to bounce back from her 2013 worlds flop.
RUTA MEILUTYTE (LTU) -- Having claimed both the world and Olympic 100m breaststroke title before her 17th birthday, the Plymouth-based 18-year-old arrives in Kazan having set both the 50m and 100m world records in Barcelona two years ago.
She trains in the same facility as British diver Tom Daley and is focused on defending her Olympic title in Rio de Janeiro, so will not want to yield her world crown to her rivals in Kazan.
She is also the only swimmer in history to hold Olympic, World and European titles at both senior and youth level at the same time, after completing her set with victory at the Youth Olympic Games in Nanjing last year.
FLORENT MANAUDOU (FRA) -- With world and Olympic 200m freestyle champion Yannick Agnel sitting out Kazan to recover from a chest infection and after the tragic death of Camille Muffat earlier this year, Olympic 50m freestyle champion Manaudou will lead the French charge for medals in Kazan.
The 24-year-old brother of 2004 Olympic 400m freestyle champion Laure Manaudou is the man to beat in the sprint having posted the fastest time of the year and he beat Brazil's world champion Cesar Cielo at the French nationals in July when he clocked 21.57sec.
Manaudou won four golds at last year's European championships in Berlin but faces tough competition over 50m from Cielo, Japanese pair Shiniri Shioura and Katsumi Nakamura who have all gone under 23 seconds this season.
VLADIMIR MOROZOV (RUS) -- In front of his home crowd, the University of South California student will be looking to go one better than his 50m freestyle silver from Barcelona two years ago and the Russian has been showing fine form on the road to Kazan.
The 23-year-old won a 4x100m freestyle bronze with the Russian team at the 2012 Olympics, but he has been improving his times.
He has posted the fastest time for 2015 for the 100m freestyle and is slower only behind Manaudou over the shorter distance and he beat Olympic champion Nathan Adrian over 100m earlier this month.
He has yet to win an Olympic or world gold, but he is one of the leading contenders for the hosts and is sure of plenty of vocal support in Kazan.
And a young talent to watch out for:
SIOBHAN-MARIE O'CONNOR (GBR) -- The British teenager is a name to mark in the women's 200m IM and the Commonwealth champion wants to push on from her Glasgow 2014 victory by improving on her Barcelona 2013 performance when she finished last in the final.
"I felt I didn’t earn my place in the final. My time just wasn't fast enough. My programme at Bath has been really good for me and I’ve made some big gains since then," said the Bath University student, who also won silver in both the 100m butterfly and 200m freestyle in Glasgow.
"Everything is coming together and I’m really looking forward to Kazan."