The Sounders beat Columbus 2-0 as their starters played a preseason-high 75 minutes.
Fredy Montero scored the go-ahead goal in the 54th minute.
Midfielder Cordell Cato added a goal in the 114th minute of the 120-minute game to clinch Seattle's first preseason win following two 1-1 ties.
Goalkeeper Michael Gspurning played the first 90 minutes of the shutout and Bryan Meredith played the final 30.
