A Cascadia rivalry match between Portland Timbers 2 and Seattle Sounders 2 highlights the Third Round of the Lamar Hunt US Open Cup, which will be played on May 27.

T2 beat the Michigan Bucks on the road on Tuesday, while S2 needed extra time to beat the Kitsap Pumas on Wednesday. The May 27 match is set to kick off at 1 pm local time (4 pm ET) at Starfire Stadium in Tukwila, Washington.

Both in their inaugural season, the sides have already squared off once, with the Sounders taking a 2-1 win in front of 2,304 fans on April 11 at Starfire Stadium. The clubs are scheduled to meet at Portland's Merlo Field on Friday, May 22, five days before their Open Cup match.

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The other MLS-operated club to play in the Third Round are the Real Monarchs, who will host Rocky Mountain foes Colorado Springs Switchbacks at Rio Tinto Stadium.

The Third Round features seven USL vs. NASL matchups, and the winners of the 15 matches will join the 17 US-based MLS squads in the tournament's Fourth Round, to be played June 17. The draw for the Fourth Round will be announced the night of May 21.

The full Third Round schedule, with home teams listed first: