The key issues of local note were MLS Sounders and MLS Timbers being paired at 7:30 p.m. June 16 at Starfire, and the third-round S2-T2 winner going on to Real Salt Lake.
Here's some of the post from U.S. Soccer:
U.S. Soccer unveiled the potential Fourth Round pairings and hosting scenarios for the 2015 Lamar Hunt U.S. Open Cup. The Fourth Round, scheduled for June 16-17, marks the opening stage of the tournament for the 17 domestic Major League Soccer (Division I) clubs, joining the 15 winners from the Third Round played May 27.
With an uneven amount of MLS clubs entering the competition in the Fourth Round, 15 of 17 MLS teams were paired geographically to a specific Third Round matchup, while two MLS teams, Seattle Sounders FC and Portland Timbers, were paired together to complete the bracket. Instances where a logical geographic fit didn't exist were resolved by random selection. Teams with an ownership affiliation (Portland Timbers and Portland Timbers 2, Real Monarchs SLC and Real Salt Lake, Seattle Sounders and Seattle Sounders 2) are precluded from being paired until the Final.
Home teams are determined by a random selection process among those clubs that have applied to host and whose venues meet the minimum tournament requirements.
Thursday's draw was conducted with two-time U.S. Open Cup champion and former Chicago Fire midfielder Logan Pause serving as the official witness as matchups for June 16-17 were determined.