NO. 1 PORTLAND TIMBERSAT NO. 4 SEATTLE SOUNDERS FC7 p.m., CenturyLink Field.TV: NBCSN. RADIO: 97.3 FM.CLUB LEADERS: For Portland: G 10, Diego Valeri; A 13, Valeri; S 72, Valeri; SOG 26, Valeri; GAA 0.97, Donovan Ricketts. For Seattle: G 9, Eddie Johnson; A 8, Mauro Rosales; S 61, Lamar Neagle; SOG 27, Johnson; GAA 1.00, Marcus Hahnemann.HEAD TO HEAD: Seattle leads the MLS series 3-2-3. The teams went 1-1-1 this season, with the Sounders going 1-0-1 at home. NOTES: This is first of a two-game, aggregate-score Western Conference semifinal series. The first leg can end in a draw. No special status is given to road goals. The series winner advances to the conference finals against the winner of the series between No. 2 Real Salt Lake and No. 3 Los Angeles. … In the regular season, Portland won the West with a 14-5-15 record. Seattle was fourth at 15-12-7. … The Sounders went 10-2-5 at home; the Timbers were 2-4-10 on the road. … Portland led MLS with a plus-21 goal differential. The Timbers were second best in goals allowed and third in goals scored. … Portland also led the league with 15 shutouts, including five in their last six games. … Hahnemann will start in goal for Seattle after No. 1 keeper Michael Gspurning was issued a red card for handling the ball outside the box Wednesday in the 2-0 knockout-round win over Colorado. … NFL lines and numbers will be on the pitch due to the Seahawks-Tampa Bay game at the stadium Sunday afternoon. … Sounders Lamar Neagle and Eddie Johnson would be suspended for the second leg if awarded yellow cards in this match. … The referee is Baldomero Toledo.QUOTABLE: “They’re more experienced (with 11 playoff matches over five seasons). But if you’re looking at 2013, we’ve had a very good year. That’s what we’re focused on now. Our group knows that if we play well, that we can beat anyone, home or away.” – Portland coach Caleb Porter on the Timbers’ first MLS playoff appearance.NEXT: The resolution game of the series starts at 8 p.m. Thursday at Jeld-Wen Field in Portland.