Thomas Muller was among the goalscorers as the Vancouver Whitecaps thrashed the San Jose Earthquakes 4-1 to edge closer to Major League Soccer's Western Conference crown on Sunday.

Former Germany and Bayern Munich star Muller steered home a 57th-minute strike from the edge of the penalty area to continue his rich vein of goalscoring since moving to MLS.

The 36-year-old has netted six times in seven appearances in all competitions for the Whitecaps, whose victory on Sunday propelled them to joint top of the Western Conference.

The Whitecaps are now level on 60 points with San Diego but have played one game less. The Whitecaps will clinch the conference if they win their two remaining regular season fixtures.

Vancouver were set on their way to Sunday's win after a well-worked goal from Rayan Elloumi opened the scoring on 39 minutes before Muller doubled the Whitecaps lead after half-time.

US international Sebastian Berhalter then rifled home spectacular long-range efforts in the 74th and 92nd minutes to round out the scoring after Beau Leroux's 89th minute consolation for San Jose.

Vancouver's victory meanwhile meant that sixth-placed Austin FC and the seventh-placed Portland Timbers have both clinched postseason berths.

Playoff-bound Los Angeles FC notched their fifth straight victory, 1-0 over Atlanta United.

Denis Bouanga delivered the game-winner in the 86th minute, firing a deflected ball into the bottom right corner for his 24th goal of the season -- tying him with Lionel Messi atop the scoring chart.

LAFC are fourth in the Western Conference, four points off the pace, but have played two fewer games than San Diego and one fewer than Vancouver.