Astralis needed overtime on its second map to complete a 2-0 sweep of Ninjas in Pyjamas on Wednesday as play began in the BLAST Premier Fall Finals.

The three other opening matches in the $425,000 Counter-Strike: Global Offensive event also ended with 2-0 scores. Natus Vincere beat BIG, Heroic topped FaZe Clan, and Team Vitality downed Team Liquid.

All matches in the double-elimination tournament are best-of-three, including the grand final on Sunday. The winning team will earn $225,000 and a berth in the BLAST Premier World Final, scheduled for Dec. 14-19. The runner-up will receive $85,000.

Astralis opened with a 16-7 win on Nuke, then edged Ninjas in Pyjamas 19-16 in overtime on Overpass.

Kristian "k0nfig" Wienecke paced Astralis' all-Danish team with 60 kills and a plus-24 kill-death differential. Swedes Nicolas "Plopski" Gonzalez Zamora and Hampus "hampus" Poser each had 38 kills and a minus-5 K-D differential for NiP.

Natus Vincere prevailed 16-4 on Dust II, 16-11 on Nuke. Ukraine's Valeriy "B1T" Vakhovskiy was the star for Natus Vincere with 47 kills and a plus-27 K-D differential. Germany's Johannes "tabseN" Wodarz topped BIG with 28 kills.

Heroic won two tight maps against FaZe Clan, 16-14 on Mirage and 16-13 on Nuke. Martin "stavn" Lund and Rasmus "sjuush" Beck each amassed 46 kills for Heroic's all-Danish side. Canada's Russel "Twistzz" Van Dulken produced 46 kills for FaZe.

Vitality handled Liquid 16-10 on Mirage and 16-7 on Dust II. Mathieu "ZywOo" Herbaut posted 49 kills and a plus-24 K-D differential for Vitality's all-French squad. Gabriel 'FalleN' Toledo led Liquid with 33 kills and a minus-7 K-D differential.

In the upper-bracket semifinals on Thursday, NaVi will oppose Heroic, and Vitality will meet Astralis. In the lower bracket's first round on Friday, BIG will square off with FaZe, and Liquid will match up with NiP.