World Grand Prix star Ricardo Pietreczko was dumbfounded after realising that he had forgotten the rules of the tournament, which are much different to any other darts event.

The German was taking on four-time world champion Raymond van Barneveld and had put himself in the ascendency, taking the first set in a first-to-two format.

Despite dropping the first leg in the second set, Pietreczko returned with the throw and got off to the best start possible – hitting treble 20.

Only for the 29-year-old to swiftly remember that he was playing in the only double-start tournament in the PDC calendar.

This means that players must begin and finish on either a double or the bull. At the event, players only start scoring points in a leg once they hit a double, with the value of their opening double counting as their first scoring dart.

In any other competition, Pietreczko’s treble 20 would have been ideal, but at the World Grand Prix his effort did not count for a single point.

He laughed off the effort as the crowd roared to mock Pietreczko, who went on to hit single 19 twice for a dismal opening score of 38.

Pietreczko lost that set as Van Barneveld forced a decider, but fortunately for ‘Pikachu’ he came out on top, whitewashing the veteran in the final set despite controversially deciding to bust on 81.

He hit a maximum to set up 81, but decided to bust and put himself back at the same number to go out on, eventually sealing the win via double 20.

Pietreczko is not the first, and certainly won’t be the last, to forget the World Grand Prix rules which are wildly different from anything else on the professional tour.

The competition is often described as marmite because players either love or hate it. In every single tournament, apart from the World Grand Prix, only one double has to be hit. To win any leg in the World Grand Prix, you have to hit two doubles. A facet that can often be forgotten, as illustrated by Pietreczko at the oche.