Columbus Crew and Portland Timbers both hold two-goal leads after the first legs of their MLS Conference finals.
Justin Meram scored after just nine seconds as the Crew beat New York Red Bulls 2-0 in the Eastern Conference, while Timbers beat FC Dallas 3-1 in the West.
Meram's goal was the fastest scored in MLS play-off history and put the Crew in a strong position to advance to the league decider.
Kei Kamara scored the second after 85 minutes as Red Bulls were held scoreless for the first time since May 24.
In the Western Conference, Liam Ridgewell, Dairon Asprilla and Nat Borchers all found the net as the Timbers beat FC Dallas.
Former Aston Villa, Birmingham and West Brom defender Ridgewell put the Timbers ahead in the 23rd minute with his first goal of the season.
Asprilla doubled the advantage before David Texeira scored in the 61st minute to narrow it for Dallas, the West's top seed in the play-offs.
However, Borchers added a stoppage-time third for Timbers to give them a two-goal lead.
Both second legs take place next Sunday before the final on December 6.