Bath swimmers Siobhan-Marie O'Connor and Calum Jarvis will become rivals this weekend when they contest the British Gas SwimBritain challenge in Loughborough.
O'Connor will join forces with Commonwealth 50m butterfly champion Fran Halsall, James Guy and Aimee Wilmott in the England team for the special training exercise and some friendly competition as they prepare to represent their nation in Glasgow this summer.
Facing them on the starting blocks will be Welsh swimmers Rob Holderness, Jarvis, Jemma Lowe and Tom Laxton. Scotland - who do not have the services of Michael Jamieson on this occasion - will complete the trio of teams competing in the Battle of SwimBritain race and feature Robbie Renwick, Craig Benson and Craig McNally.
SwimBritain is a four-person relay where each team member swims 250m four times around a specially-designed course in a dedicated 50m pool.
Taking place at locations around the country from August, it will give the public a chance to join the Battle of SwimBritain athletes and many more to complete the challenge and celebrate a summer of swimming.
The Battle of SwimBritain race will kick-start their training for the SwimBritain challenge, as well as give the teams a sneak peak at how they measure up against each other as individual nations.
Halsall said: "I'm really looking forward to teaming up with my fellow English swimmers for the Battle of SwimBritain.
"As elite swimmers we're all naturally competitive, so there will definitely be an element of sizing up the other teams, especially as it's the first time we've competed as individual nations this season.
"Winning medals at a national and international level is obviously the pinnacle for all elite swimmers, but it's the hours of training and preparation in the pool that make it possible to go out there and give your best performance."
Registration for British Gas SwimBritain is now open and teams can sign up to join one of the country's swimming stars to complete the challenge at the end of the summer.
Available for all participants that sign up, the SwimBritain Training app will help track, log and monitor progress as swimmers around the country prepare to take on the 1000m water challenge.
Also available are instructor-led sessions for all SwimBritain participants at one of over 120 pools nationwide, as well as online training materials at swimbritain.co.uk.
Find your nearest venue and more by visiting swimbritain.co.uk or following @BGSwimming and Facebook.com/BGSwimming.
