The reeling Warriors have now gone 9-18 since a 12-3 start and fallen to the outside looking in at the Western Conference play-in race.

Jayson Tatum scored 22 points, Kristaps Porzingis had 18 and the Boston Celtics handed the Golden State Warriors their most lopsided home loss in 40 years with a 125-85 victory.

Minneapolis, Minnesota, USA; Golden State Warriors head coach Steve Kerr looks on against the Minnesota Timberwolves in the second half at Target Center. Mandatory C

SAN FRANCISCO — The Celtics have hit a slog in their schedule as it’s clear they haven’t been playing their best basketball of late. While they still have the second-best record in the East, they’re just 8-8 over their last 16 games as inconsistencies and other issues have bogged them down.

In San Francisco, the first of three stops on a West Coast swing, the Celtics led by 15 at the half and never looked back.

The Boston Celtics began January’s second West Coast road trip on Monday evening, facing off against the 21-20 Golden State Warriors at the Chase Center in San Francisco. The Celtics and Warriors would square off on Martin Luther King Jr.