With multiple lineup changes on both sides, a wild night was expected between the Sounders and FC Dallas on Saturday. From the keepers to the forwards, there were plenty of plays that conjured a reaction from the 31,785 in attendance on a pristine spring night. The final, after a tense series during a Dallas corner kick, was a mix of relief and celebration of a 2-1 Sounders win at Lumen Field. The Sounders are now on a 20-match unbeaten streak at home (15-0-5) while Dallas hasn’t won in the stadium since 2011. Dallas swarmed the Sounders (6-1-1) from the opening kick. Three dangerous situations in the box missed and one that should’ve been a solid attempt was bobbled out of play. A strong sense that a Dallas goal was imminent only grew. Then Sounders center back Jackson Ragen sent a long ball to the right wing for an awaiting Jordan Morris. The forward quickly directed the ball into space in the midfield for Jesús Ferreira to mash into the back of the net in the 15 th minute.…