With the score tied at 1-1, Jansen came running out of his area to clear a pass that had been played towards his goal and got knocked over in the process by Amsterdamsche forward Marciano Mengerink.
While Jansen was face down on the ground, the ball flew almost the entire length of the pitch, bounced over Amsterdamsche goalkeeper Gijs van Zetten and nestled in the back of the net.
Still on the ground following the challenge, Jansen – who looked in disbelief when he realized what had happened – was then mobbed by his teammates as they celebrated his goal.
It was a crucial goal, too, as it set Noordwijk on its way to a 3-1 win.
In a post-match interview with Dutch outlet Voetbal in de Bollenstreek, Jansen said he didn’t see his goal “at all” due to the collision with Mengerink.
“Yeah, I really wish I’d realised it myself,” he laughed. “It was not a conscious goal, I can make it more beautiful than it is, but it was not a conscious one.
“Of course I like to stop balls as a goalkeeper but it is also fun to score a goal every now and then. It doesn’t happen that often so you have to enjoy it.”
Jansen added that he has previously scored while playing out on the pitch, but said this was his first goal as a goalkeeper.
“I hope there is a good video of it!” Jansen joked.