There's still the pesky matter of the Seattle Sounders and Portland Timbers winning their third-round games, but the Cascadia Cup rivals are set to play one another in the U.S. Open Cup for the fourth time since 2007 assuming they both advance. Also for a third time in four years, the Sounders would be paying a visit to Jeld-Wen Field. The Sounders have won all three times, although the 2010 game went to a penalty kick shootout.
In the unlikely scenario that Cal FC manages to beat the Timbers, the Sounders would host that game. Either way, the fourth-round game is scheduled to be played on Tuesday, June 5. The site for the highly unlikely scenario of a Silverbacks-Cal FC match is TBD.
Unlike the two previous U.S. Open Cup meetings between the rivals, both teams are now in MLS. (In the 2007 encounter, both were USL teams.)
This would mean the Sounders and Timbers will play at least four games against one another this season, with three of them being in Portland. The Sounders will also play at Portland on June 24 in MLS play and won't host the Timbers until Oct. 7.