Football fans say they will ask Uefa to make Wales the home team for their clash against Russia on Monday - so the game's official hashtag will be #walrus.
Fans discussing games on social media have been combining the names of the two teams taking part to make a new hashtag, such as #engwal for when England played Wales.
And ever since the groups for Euro 2016 were drawn with Russia and Wales winding up in the same group, fans have been looking forward to the #walrus game.
Unfortunately for them, Russia are the designated home team for the clash in Toulouse - so officially the match will be known as #ruswal on Twitter.
Many football fans have already expressed their regret, with Alex Shaw from ESPN tweeting: "Disappointed that Euro 2016 is classing it as Russia v Wales. Could have had the hashtag #WALRUS otherwise."
Disappointed that Euro 2016 is classing it as Russia v Wales. Could have had the hashtag #WALRUS otherwise.— Alex Shaw (@AlexShawESPN) June 14, 2016
Twitter user @Dewi_Mawr added: "Worst thing about this isn't @FAWales not playing in red; it's that we won't see WALRUS trending on social media!"
Meanwhile, a group of Wales fans in Toulouse for the game jokingly said they would lobby Uefa to get the situation rectified.
Joe White, 19, from Cardiff, said: "What a missed opportunity really, I'll be dropping them a tweet later on to see what we can sort."
Rhys Morgan, 20, also of Cardiff, said: "Everyone will probably be calling it Walrus anyway regardless of what they are officially using as a hashtag."