The three-time major victor took to social media to reveal the fears he had in the immediate aftermath of the accident, which required six stitches.
The 45-year-old revealed that an elbow injury suffered while coaching an amateur had him fearing the worst, but will only be out of action for less than two weeks.
Despite the possible seriousness of the situation, Harrington was still able to crack (ouch) a few jokes at his and the amateur's expense on Twitter.
"Yesterday I picked up an elbow injury at a golf outing in Washington DC", the three-time major victor wrote on his personal website.More news: Australia look to find form in ICC Champions Trophy against Bangladesh
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"Yesterday I picked up an elbow injury at a golf outing in Washington DC", Harrington wrote on his personal website.
"My initial thought was that the elbow was shattered and it was the end to my competitive playing career". I almost fainted with the pain and shock.
Harrington said nothing was broken but that he got six stitches.
He said he'll likely be out 12 days.