Amateur clubs are increasingly successful in the KNVB Cup, how is that possible?

Disbelief joy and tears at Hercules after cup win over

Hercules beating Ajax and forcing extra time against SC Cambuur, Spakenburg beating FC Groningen and FC Utrecht: it is no longer an exception for an amateur club to go far in the KNVB Cup. In our province alone, an amateur club has reached the last 16 of the cup eight times since 2010. This happened only once between 1970 and 2010. How is that possible?.

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