3 keys as Sounders look to clinch win over FC Dallas in Western Conference semifinals

For the first time ever, the Seattle Sounders go into the second leg of a playoff match with a whopping 3-0 advantage. The memorable seven-minute stretch in the first leg in which the Sounders scored all three of their goals is going to be the stuff of legend, especially if they make it even further in the playoffs.

But let’s not get ahead of ourselves, because the Sounders still have 90 hard-fought minutes ahead of them. FC Dallas is still the Supporters Shield champion, and it will be bringing everything they have against Seattle. Dallas has to overcome the deficit, and if it show sthe same defensive frailties as in the first leg, it’ll be quite the task.

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Here are three things to consider when the Sounders take on FC Dallas in Frisco, Texas at 6 p.m. Sunday on KIRO Radio 97.3 FM:

• Dallas will be 100% attack. As I noted before the first leg, FC Dallas is most fragile on defense when its attack is also weak. After the midseason transfer of Fabian Castillo and the injury to Mauro Diaz, Dallas’ attack has taken some pretty rough hits in 2016. But as their two-trophy haul so far shows, it’s a resilient team. In Seattle last week, Dallas played something like a 5-3-2, clearly communicating its plan to “park the bus.” The problem was that coach Oscar Pareja’s team isn’t used to such a formation, and the Sounders exploited that weaknesses to devastating effect. I can almost guarantee that Dallas will bring out its usual 4-4-2 on Sunday, but Pareja will be having his outside midfielders pushing forward on the counter often.

• The Sounders won’t be bunkering down. Due to the rules of this round of the playoffs, away goals count more than home goals in case of a tiebreaker. If the Sounders manage to score one goal in Dallas, the home side will need to score five in order to beat Seattle. Even if the Sounders are still without Roman Torres in the starting XI, last weekend’s defense showed that it can go toe to toe with Dallas’ attackers. I don’t expect head coach Brian Schmetzer to send his boys flying out of the gate, but they won’t be parking the bus either. I expect a very similar starting XI to the one that ran out last weekend, with Nelson Valdez leading the line and hoping to continue his playoff scoring streak.

• Will Dallas get its creativity back? After the loss of Diaz earlier this season, it’s been much more difficult for FC Dallas to create lightning-quick counter attacks through midfield. Other than their CONCACAF Champions League match, Dallas has only played a 0-0 draw with Los Angeles and last weekend’s 3-0 loss since losing Diaz against Seattle on Oct. 16, so it hasn’t exactly had time to get things sorted out. Michael Barrios is quick and great on the wing, but he’s not the same kind of midfield maestro as Diaz, who leads the team with 10 assists in 2016. Curiously enough, Dallas hasn’t really started Mauro Rosales this season despite his tremendous creative abilities. The former Sounder can still pass and deliver a cross or set piece on par with some of the best in the league, but he’s definitely a step behind his best and has appeared off the bench more often than not this season. Whether or not Rosales is the key to Dallas figuring out new ways to create goal-scoring opportunities, it’s going to need somebody who can give it a chance to dig out of the three-goal hole.

Spenser Davis also covers the Sounders for Sounder at Heart.