The apology only came after CNN identified and contacted the man.
The clip is originally from a 2007 appearance Trump made on WWE's WrestleMania in which he tussled with wrestling CEO Vince McMahon. (Fun fact: Linda McMahon, Vince's wife, is now the small-business administrator in Trump's cabinet. Good times.)
The network denounced Trump's tweet, saying it encouraged violence against reporters.
The wrestling video was originally lifted from a post on Reddit for Trump's fans. The clip, which had no sound in the Reddit version, was posted by a user named “HanAssholeSolo.”
"Congratulations /u/HanAssholeSolo, your dankery has been tweeted by the President of the United States," a fellow redditor commented on the post after Sunday's tweet.