SINCE MAJOR LEAGUE SOCCER'S expansion into the Pacific Northwest has brought us the intensity of the Cascadia Cup rivalries, those games often had more to do with regional bragging rights than actual places atop the standings. 

Rarely since Portland and Vancouver joined Seattle in 2011 have two of the teams been in contention at the same time. But that appears to be changing this year, which is why the Sounders' visit to the Whitecaps (Saturday, 7pm ET, MLS DirectKick) is our choice for MLS Game of the Week.

Seattle’s status as a contender is expected. The Sounders (5-3-1, 16 points, third place in the Western Conference) won the Supporters’ Shield and U.S. Open Cup a year ago and started this season expected to contend for MLS Cup.

But Vancouver’s place among the leaders has caught many by surprise. The Whitecaps (6-3-2, 20 points, tied with Dallas for first) finished fifth in the West a year ago and with the conference now stocked with recent MLS Cup participants Houston and Kansas City, not to mention the reigning champion Los Angeles Galaxy, it wasn’t expected to move much further up the standings. 

The combination of Chilean playmaker Pedro Morales (two goals, four assists) and offseason acquisition Octavio Rivero (six goals) has made the Whitecaps one of the more dynamic and efficient teams in MLS and will provide ample test for a Sounders backline that has looked stout some weeks and leaky in others—such as last week when the team fell to the Columbus Crew 3-2.

THE SUBPLOTS

While the Whitecaps have four more points than Seattle, Sigi Schmid's team has a pair of games in hand and will have a chance to make up ground. So the onus is on Vancouver to get three points in this one, especially since this game is being played in British Columbia. 

The Whitecaps also need to show it can beat a good team. To Vancouver's credit, it has taken the next step that teams must make on the path to becoming a contender—beating teams it is supposed to beat. But victories over the likes of Orlando, Chicago, and Philadelphia only takes a good team so far.

Two weeks ago Vancouver lost at home to D.C. United, currently sporting the best record in MLS. While the Canadian side does have a win over the Galaxy in 2015, beating the Sounders would send a signal that it is a legit contender in the crowded West.

For the Sounders, a loss would put it seven points back, something it is obviously looking to avoid.

PLAYERS TO WATCH

Any match with this many scoring threats puts the attention on them. Morales and Rivero will look to test Seattle's center back combo of Chad Marshall and Brad Evans. At times, such as a six-game stretch earlier this season when it only allowed three goals, the Sounders' defense has looked elite. But games like the one against the Crew and earlier this year against San Jose have cost the Sounders points in the standings. How this matchup goes will go a long way in deciding a winner.

The Whitecaps defense has posted five shutouts so far this season but it hasn't faced a scoring combo like the Sounders' duo of Clint Dempsey (seven goals, four assists) and Obafemi Martins (six and two), who are the two of the top three scorers in MLS. The one reprieve for Vancouver is Martins may not play because of a bone bruise in his leg and if he does see the field he may not be at his best.

THE X-FACTOR

When he’s healthy and completely in-form, the Sounders' pitbull midfielder Osvaldo Alonso is still one of the best at his position in MLS. The former Cuban national teamer missed the first part of the season recovering from surgery but since returning six games ago he had helped elevate the Sounders on both sides of the field. 

Alonso is capable of dominating the midfield and neutralizing Whitecaps playmaker Morales, making it easier for the Sounders to starve Rivero of service. 

PREDICTION

Vancouver is much improved over the last year and playing at home. But it’s hard to imagine the Sounders laying stinkers in consecutive weeks so, 2-1 to the visitors.

Brooke Tunstall is an American Soccer Now contributing editor and ASN 100 panelist. Follow him on Twitter.