Crap. I would use other words but I dislike using those. Let's just say this was the worst performance since the last time Portland lost 4-2 at RSL. Everything that could go wrong did, Portland's weaknesses were exploited and almost every mistake was compounded by another mistake.
What went wrong
Set Piece defense seems to be Portland's Achilles' Heel. They were 18th in the league in goals given up on set pieces and RSL was near the top of the list. Giving up set pieces in general is the key and Portland had too many silly fouls and conceded to many corner kicks.
Portland's dominant midfield and the pressure they bring were too easily bypassed. RSL found the holes in the formation and easily exploited them and this forced the Diego Chara and Will Johnson to constantly recover quickly to put out fires which lead to them having no energy in the final stages of the game.
Portland's offense died just as it entered the attacking third of the field. Movement off the ball was nonexistent which was evidenced by Darlington Nagbe constantly pulling up and having to dribble by three or four players before he was able to make a pass, which was usually laterally or backwards. At one point Jose Valencia received the ball with only the two RSL CBs in front of him and as he dribbled towards the goal only RSL players tracking back were in the picture. It was 6 or 7 RSL players and one Portland player in the final third.
What went right
This is hard as not much went right for the Timbers but there are a couple things that they can hold onto as they prepare for the second leg. Darlington Nagbe found space on the field to turn and dribble at the defense it is just too bad that no one was making runs to get open when he did. If Nagbe can find space again in the second leg he could be the reason Portland pulls off the comeback.
Frederic Piquionne's goal was exactly what Portland needed at a time when all seemed lost. Piquionne not only scored the goal but it really felt like Portland had a burst of energy once he came on. His goal is exactly how you need to attack a team which has been shutting down passing lanes all night. Hit the early crosses into the box and win the header and Piquionne is the best forward we have to win those kinds of balls.