The Seattle Sounders are taking on the rival Portland Timbers on Sunday (7 p.m. PT; FS1, 950 KJR AM, El Rey 1360 AM) at Providence Park. Here are three matchups to watch:

Cristian Roldan vs. Eryk Williamson

PORvSEA Three Matchups Roldan-2

Fresh off winning the Concacaf Gold Cup together with the United States national team, the Roldan and Williamson are pivotal to their respective teams’ success. Each has a legitimate shout for MLS Best XI this season and are influential on both sides of the ball. Whichever player can get the better of the other is likely going to help his team walk away with three points.

Brad Smith vs. Yimmi Chará

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In what has to be one of the fastest matchups in MLS, Smith and Chará will be flying up and down the Sounders’ left flank all evening. Smith loves to join the attack, but he will have to be mindful of Diego’s younger brother, especially in transition moments. The Colombian has the pace and the skill to burn Seattle if he gets into open space, so Smith will need to do his fair share of defensive work while also forcing Chará deeper and keeping him honest.

Yeimar vs. Felipe Mora

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Yeimar has played at an MLS Defender of the Year level this season, and his next challenge will be keeping Mora off the scoresheet. The Chilean international is currently one of the most in-form strikers in the league, as he enters having scored in four of his last five matches. Yeimar & Co. on the back line will be looking for a similar stout defensive performance as they had in their 3-0 Leagues Cup Quarterfinals win over Tigres midweek.