The Seattle Sounders moved into the Western Conference playoff spots in the MLS, defeating the Vancouver Whitecaps 4-0 on Tuesday.

The Sounders took the three points via a double from Raul Ruidiaz along with goals from Nicolas Lodeiro and Alex Roldan, in this MLS season's first match of the Cascadia Cup.

In the rivalry that dates back to the NASL in the 1970s, the Sounders claimed their 18th win over the Caps in the MLS era with Tuesday's victory.

Ruidiaz was instrumental for Seattle in scoring the opener, breaking clear and playing Fredy Montero in, before he was brought down by Cody Cropper. Lodeiro converted from the penalty spot.

He pounced again in the 28th minute, reacting quickest to Jimmy Medranda's heavy first touch to finish, before scoring a second in the 54th minute. Alex Roldan added a fourth in the 89th minute.

After winning two of their opening seven league games, Brian Schmetzer's side have won four of their past six since claiming the CONCACAF Champions League title in May.

Seattle are now seventh in the Western Conference on 19 points, moving ahead of the three-way tie on 18 points between Houston Dynamo, Minnesota United and Colorado Rapids, with a game in hand as well.