The Deadpool actor shared a graphic that said: "Wrexham United" with the caption, "Yes, this is happening."
McElhenney shared the image saying 'change is in the air', a hint that all wasn't as it seemed with the duo later revealing that the post was in reference to a shirt sponsorship deal with United Airlines.
While the whole mishap was scripted for comedic purposes, Reynolds and McElhenney shared a video in which they played on their lack of British football knowledge to fully reveal the news of the lucrative new endorsement.
Here's what the Hollywood duo said about the tweet in the light-hearted, scripted video.
McElhenney: That tweet needs some explanation.
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Reynolds: We stepped in it. It was bound to happen.
McElhenney: When we tweeted Wrexham United, we forgot to include a super important ampersand.
Reynolds: It should have read Wrexham AND United because Wrexham Is going to be sponsored by United Airlines. It's the front of shirt, which is super exciting. We just really wanted to share this."
McElhenney: Yeah, we will not now, nor will we ever change the name of the club.
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Reynolds: We would never do that.
McElhenney: It's probably illegal anyway.
Reynolds: Yeah, if it's not illegal it should be. Let's make it illegal. If we can do that, legally.
McEllhenney: We are very sorry for the confusion.
Reynolds: But we're mostly excited. United, that's a major airline. It's a banner day for the team and the town.
McElhenney: The city.
Reynolds: Right, Wrexham City. I still prefer town.
McElhenney: I do too, but I think we've got to button this up a bit, Ryan. We are now in the EFL.
The pair then attempted a high-five but missed each other, leading to an awkward end to the video.