Roberto Di Matteoâ€™s Blues opened up their 2012 Herbalife World Football Challenge at CenturyLink Field with a four-goal blitz in the first half but the Sounders made life difficult, scoring two of their own in the opening 45 minutes.
It looked it may have been a rout but Sigi Schmidâ€™s Sounders fought back through Fredy Montero just prior to the 15-minute mark with a neat finish from the edge of the area. In the 32nd minute, Seattle were back on level terms when Montero grabbed his second a low, left-footed shot inside the far post from the right side of the box.
Five minutes before half-time, Chelsea wrestled back the lead with another new signing Marko Marin cutting in from the left and hammering home with the aid of a slight deflection.
The scoring was complete in the 44th minute when Lukaku received a ball from Marin, rounded Seattleâ€™s keeper, and slotted home to give the Blues the win.
Chelsea will stay in Seattle for two days of training before heading to New York City for their second match in the World Football Challenge on Sunday, July 22 against Paris Saint-Germain at the new Yankee Stadium.