The LA Galaxy were "outplayed across the board" in their chastening 4-0 home defeat to the Seattle Sounders on Sunday, believes head coach Greg Vanney.

The MLS Cup holders remain rooted to the bottom of the Western Conference with just 15 points from 25 games, following their second-heaviest defeat of the campaign.

Only against the New York Red Bulls, in a 7-0 road loss in early May, have the Galaxy been more comprehensively beaten in MLS this year.

Julian Aude's 25th-minute own goal set Seattle on their way to victory in California, with Danny Musovski making it 2-0 on the rebound late in the first half.

Musovski got another close-range tap-in early in the second half, then 18-year-old Synder Brunell marked his MLS debut with a goal in the 85th minute.

Seattle are now unbeaten in 10 games across all competitions since losing 2-0 to Paris Saint-Germain at the Club World Cup in June, scoring 26 goals in their last eight outings. 

And Vanney believes his men were nowhere near the level required to match a team that sit fourth in the Western Conference.

"There have been a few games over the course of the season where I felt we were just outplayed across the board. This was one of them," Vanney told reporters.

"I don't know if it's four games in a short period of time, one day less rest... We can talk about all that stuff, but we never hit the necessary speed on the night in many regards. 

"Therefore, I felt like we got pretty dominated in a lot of areas of the field and in the game throughout the course of the night."

Galaxy captain Maya Yoshida concurred, saying: "Today, no one had the standard level needed for the game, none of us, to be honest."

The Galaxy do have a Leagues Cup quarter-final against Pachuca coming up, having scored 10 goals in three group-stage matches in that competition (4-0 versus Santos, 1-1 versus Cruz Azul, 5-2 against Tijuana).

But Yoshida believes Seattle were on another level to the Galaxy's recent opponents, saying: "Seattle are different. They're a much better team, to be honest."

The Sounders' next MLS game is against one of the three teams above them in the Western Conference, as they visit Minnesota United on Saturday, before taking on Puebla in their own Leagues Cup quarter-final.