Should both Great Britain and Ireland force their way through their pool campaigns in Rio, one Antrim household will have divided loyalties.
Lisnagarvey’s Paul Gleghorne could then take to the pitch against his brother Mark, who will be pulling on the Team GB shirt.
Both are set to make their Olympic debuts. Mark had made the switch to Team GB in time for the 2012 Games but he was forced to sit out due to plantar fasciitis - a disorder that causes pain in the heel and bottom of the foot.
The older brother did return in time to grab a bronze medal at the 2014 Commonwealth Games.
That meant it was first blood to Mark but last year, Paul snatched back bragging rights as he and his Ireland squad denied Team GB in one of the biggest ever results for Irish hockey.
That was when they overcame Mark’s England team 4-2 to take bronze at the EuroHockey Championships.
However, Ireland ace Paul says he isn’t allowing himself to become distracted by any thoughts of ousting his brother from another major tournament.
“We have to focus on the group games first,” he insisted, “and GB are not in our group.
“We have to concentrate on taking things one game at a time. With the format the way it is, the priority is to make sure we are in the quarter final. After that you are in to one off games and w have a good record in knockout matches. Everyone in the squad is very positive about our chances.”
Paul was speaking from right in the heart of the Olympic build-up, nestled into his digs in the athlete’s village.
“There’s a good atmosphere around the place and everyone is looking forward to the games getting underway,” he said.
Mark made the switch to GB back in 2009, the same year that Paul made his Ireland debut.
He’s not the only Ulsterman to change his colours. In fact, he’s joined by three others in GB’s Olympic squad, including 32 year-old Belfast man Iain Lewers.
The former Annadale star is full of experience, having played professional hockey in England, the Netherlands and India.
Also in the squad are Cookstown duo Ian Sloan and David Ames. Two of Ulster’s brightest young talents, the pair helped Ireland to the brink of Olympic qualification for the 2012 Games. However, last gasp heartache at the hands of Korea ended the pair’s Ireland stint and both shifted allegiances.
So should Great Britain or Ireland claim success in Rio, Ulster will have played a significant part - nobody more so than the Gleghorne household.