Portland scored two goals off set pieces to take the commanding lead into the second leg while Dallas picked up a road goal from David Texeira.
Portland came out with a lot of energy and intensity in this one, forcing Homegrown keeper Jesse Gonzalez to make several early saves including one in the first minute of the match on an attempt by Lucas Milano. Portland had several other chances in the first 20 minutes of the match as they looked to gain the early advantage.
In the 23rd minute however the Timbers found the back of the net on a corner kick taken by Darlington Nagbe. The famed Dallas-killer sent a curled ball into the penalty box where defender Liam Ridgewell was able to get on the back post to slot it home for the series' first goal.
The Timbers could strike again after halftime as Dairon Asprilla scored a ridiculous goal in the 53rd minute. Asprilla took control of the ball outside of the Dallas penalty box, he made one move around a defender before sending a knuckling ball into the upper corner of the back post.
Dallas would respond ten minutes later as Mauro Diaz finally was able to get some solid passing going the flanks. In the 62nd minute, Diaz sent a threw pass to the run of Je-Vaughn Watson on the right sideline, the Jamaican then sent a one-touch pass to Texeira, who also took one touch on his shot that found the back of the net.
The Timbers weren't done unfortunately for Dallas fans on the night as they found the back of the net again off a corner kick just before the end of the game from Nat Borchers. The veteran defender got free in the box as Gonzalez and Tesho Akindele were attempting to clear the ball out.
Portland now takes their advantage to the second game of the series back in Frisco this coming Sunday.