Romelu Lukaku netted a first-half double, with all six goals coming during the opening 45 minutes. The game marked Roger Levesque's last.
In his first match as permanent manager, Robert Di Matteo gave starts to new signings Eden Hazard and Marko Marin, with highlyrated duo Joshua McEachran and Romelu Lukaku starting in midfield and up front respectively.
It was the latter pair who combined to give the Premier League side the lead after less than three minutes. McEachran trotted through a backtracking Seattle midfield to send Lukaku through on goal. The Belgium international outmuscled Jeff Parke before slotting past Bryan Meredith to put his side 1-0 up.
It was not all plain sailing, though, as Seattle could, and perhaps should, have leveled just five minutes later when Mauro Rosales took advantage of a poor punch by Hilario in the Chelsea goal to find space inside the opposition area, but the midfielder’s rushed shot failed to threaten the goalkeeper’s net.
The American opposition was to immediately rue that haphazard finishing as Hazard showed why the Premier League outfit paid out 32 million pounds for the midfielder with a glorious solo run, evading two challenges on the way, to extend his side’s lead.
The Belgium international’s celebrations were short-lived, however, as Seattle pulled one back just three minutes later when Fredy Montero intercepted a poor pass out of defence by Branislav Ivanovic to run into the penalty area and cooly finish past Hilario.
Seattle equalized on the half-hour mark, after a period of concentrated pressure which saw Alvaro Fernandez twice go close, when Montero cut inside 20 yards out and send a smart, low shot past Hilario for his, and his team’s, second of the night.
Despite their frailties at the back, Hazard was continuing to impress at the other end of the pitch for Chelsea, continually outfoxing the opposition with quick feet and awareness. But it was the other new boy to have the next telling impact as Marin cut inside from the left and curled a shot into the far bottom corner, via a sizeable deflection off Zach Scott, to restore the Blues’ lead.
And Lukaku re-established Chelsea’s two-goal advantage one minute from the break when McEachran grabbed his third assist of the game with yet another impressive through ball to allow the striker to round Meredith and pass the ball into the back of the net to end a captivating opening 45 minutes at the CenturyLink Arena.
The hosts who came the closest to opening the second half scoring when a lightning-quick counterattack saw Andy Rose whip in a low cross that was inches away from fan favourite, Roger Levesque’s toe and a surely certain third for Seattle. Levesque earlier announced his retirement following the friendly.
That was to be the last meaningful attack of a much more tepid second period, with the story of the game being Levesque's last moments as a Sounder.