Van de Pas went towards the finishing line initially but had to wait for his chance as Clemens brought the match back towards his favour but he turned it around again to see off the heavily fancied German who beforehand had been touted for a big run in the tournament.
Van de Pas claimed the first set in dramatic fashion as up to this point he only was averaging 79 and looking poor but he got over the line due to Clemens missing five set darts in the decider.
Clemens finally produced when it mattered claiming a set back taking it to nil to level the match with a 92.3 average and two 180s. Van de Pas kept the pressure on though with both players averaging in the mid 80's.
He took the set 3-1 as it looked like he was going to claim a big shock despite not playing to his best by any means. 'Big Ben' took his chances though against the heavily fancied German.
A 106 checkout from Clemens to break saw him keep the belief alive and it was now up to him to attempt to force a decider.
He cruised to the fourth set 3-1 as his average went up to 94 with four 180s as he sent it all the way. Clemens took out 75 to go ahead in the decider and he doubled his lead with a 68 checkout.
Despite that Van de Pas broke through on double six and held his throw to go one away and from there, he completed an unlikely victory.
Click here for more information on the PDC World Darts Championship, which takes place at the Alexandra Palace between December 13 and January 1.
James Wilson (89.89) 1-3 (95.67) Nico Kurz (R1)
Josh Payne (96.49) 3-0 (90.46) Diogo Portela (R1)
Gabriel Clemens (93.57) 2-3 (88.64) Benito van de Pas (R1)
James Wade vs Ritchie Edhouse (R2)
https://twitter.com/OfficialPDC/status/1207419350380154880?s=20