The series will resolve Tuesday, when Tigres visits CenturyLink Field. Seattle must make up at least one goal, and perhaps more because road goals are the first tie-breaker.
Tigres dominated in shots -- 18-3 – and the best chance came early. In the third minute, Lucas Lobos juked past Seattle sliding goalkeeper Michael Gspurning before his shot was cleared off the line by defender Leo Gonzalez.
Despite that and the parade of other opportunities that followed, it eventually began to seem the Sounders might be able to escape the series opener with a scoreless draw.
Then, about 15 minutes from the end, Tigres lifted a pass over the Seattle back line as Sounders raised their hands for an offside call. However no whistle was blown, and the ball landed at the foot of Lobos. His shot was saved by Gspurning, but the rebound went to Alan Pulido, who headed the ball into the goal.
Both teams quickly adjusted their lineups, with Tigres seeming to go for the kill with more offense, while Sounders coach Sigi Schmid countered with more defense to remain within striking distance.
Seattle accomplished that and almost more as Eddie Johnson and Lamar Neagle both had chances before the final whistle.
Seattle is off until the resolution game Tuesday. However, Tigres must return its attention to Liga MX, facing a match at San Luis on Saturday before traveling to the Pacific Northwest.
The first leg has gone final: Tigres 1, Sounders 0.
The resolution game will be played at 7 p.m. Tuesday at CenturyLink Field. Plenty of tickets remain.
I'll be back with stats and quotes as they arrive from Mexico.
89' Final Seattle sub: Martinez out, Marc Burch in.
81st minute: Midfielder Caskey out, defender Yedlin in.
74th minute: GOAL Tigres. Alan Pulido on rebound after Gspurning save. Sounders wave for offside, but replay shows it was not.. 1-0.
68' First Sounders' sub: Lamar Neagle comes in for Mauro Rosales.
Through 60: Scoreless. (Road goals are tie-breaker in CCL.)
Through 55: Sounders came out with their best few minutes of the match, but things turning back Tigres way now. Still scoreless.
Second half: ... has begun. No changes for either side.
Halftime: All possession and chances to Tigres. But it's 0-0 halfway through.
Through 30: The last 10 minutes have been better for Seattle. Still scoreless.
24th minure: Sounders waste real free kick chance as Johnson gets over and behind Tigres back line.
Through 20: Sounders feel like they're living on borrowed time, but they're still alive. Scoreless. Which they'll happily take.
First 10 minutes: All Tigres early, including a great scoring opportunity where Gspurning was beaten, but Leo Gonzalez cleared shot off the goal line. Scoreless.
First kick: ... has been struck. The 180-minute knockout stage is underway.
Pregame: The Sounders return to CONCACAF Champions League action at 7 tonight, visiting Monterrey, Mexico, to face Tigres. The game will be shown on Fox Soccer. There's no radio. I'll have blog updates here, and Twitter comments @donruiztnt.
Here are the Sounders starters:
GK - 1 Michael Gspurning RB - 20 Zach Scott CB - 19 Djimi Traore CB - 34 Jhon Kennedy Hurtado LB - 12 Leo Gonzalez RM - 14 Alex Caskey CM - 6 Osvaldo Alonso CM - 3 Brad Evans LM - 15 Mario Martinez F - 10 Mauro Rosales (captain) F - 7 Eddie Johnson Reserves: Marcus Hahnemann, Marc Burch, DeAndre Yedlin, Servando Carrasco, Andy Rose, Lamar Neagle, Sammy Ochoa.
For Tigres: GK - 1 Enrique Palos RB - 2 Israel Jimenez CB - 3 Juninho (Anselmo Vendrechovski) CB - 4 Hugo Ayala LB - 6 Jorge Torres RM - 28 Acosta CM - 18 Jose Torres CM - 16 Lucas Lobos (captain) CM - 30 Carlos Salcido LM - 10 Elias Hernandez F - 9 Luis Garcia Reserves: 15. Viniegra, 19. Pulido, 20. Veron, 21. Fernandez, 24. Rivas, 29. Duenar, 11. Damian AlvarezWeather: Partly cloudy and 61-degrees. SE wind at 6 mph. Referee: Jeffrey Solis (Costa Rica) Assistants: Osvaldo Luna; Javier Rojas Sanchez 4th Official: Ricardo Cerdas Stadium: Estadio Universitario, Monterrey Attendance: 35,000 expected (stadium holds around 41,000) Sounders FC will debut its 2013 secondary kit, Cascade Shale. Tigres will wear gold with blue.