Mr Santomartino earlier retweeted a photo of the pier, before his attempt to board it appeared on his Twitter timeline.
"Huge mistake," he tweeted, sharing the video earlier today, in a tweet that is quickly attracting attention online.
"Yeah but you gave it a crack," one man tweeted back at the reporter.
"Is that a mic in your hand," one person asked?
"Employee of the week," another person commented.
Nine Melbourne chief of staff Gillian Lantouris shared the video saying the bureau had "a very cold and damp reporter in Frankston this morning".
Mr Santomartino told 3AW this afternoon he was thankfully not hurt by his fall at the beach.
"I'm completely fine, just a bruised ego," he said.
The journalist has previously made headlines for being injured on the job.
Last year he was viciously swooped by a magpie in a suburban park, as he set up for an interview.
"Before the interview, I went for a walk and unbeknown to me, I walked by a tree with a magpie," Mr Santomartino said at the time.
"Out of nowhere, from my left hand side, I got clipped in the head.
"All I remember seeing is a flash of black and white. I flinched but it got me just above my hairline." He was left bleeding profusely from the head.
The event was particularly upsetting because the intrepid journalist said he has a fear of birds.
