Jack Eichel, Michael Amadio and William Karlsson scored for Vegas — all in the first two periods. The Golden Knights had dropped five of six overall.
The Kings had won four of five. Anze Kopitar had a goal and an assist for the Kings, and Trevor Moore also scored. Cam Talbot made 29 saves.
Thompson surrendered four goals on the Ducks’ first nine shots during a 5-2 loss Wednesday night, but then stopped 14 of the next 15. He carried that play into the matchup with the Kings and got some help from his teammates, who blocked a season-high 34 shots.
The four consecutive games for Vegas without a point — all on the road — was its longest such stretch under second-year coach Bruce Cassidy.
It was just the second regulation road loss for the Kings, who are 13-2-1 away from home.
Knights defenseman Ben Hutton didn’t play the final two periods because of an upper-body injury.
With chances at a premium during a defensive first period, Eichel took advantage of a small opening. Ivan Barbashev delivered a cross-ice pass to Eichel, who beat Talbot high from the left circle. Eichel has 40 points in 37 games.
Vegas twice extended that lead to two goals in the second period. Amadio scored off a rush after receiving a pass from Pavel Dorofeyev, and Karlsson scored his 15th goal from the slot on a pass from Paul Cotter from behind the goal line.
Cotter has four points in his past four games and eight for December. He had seven in the first two months.
Kopitar got his 14th goal at 13:07, with Adrian Kempe recording his 20th assist on the play. Kopitar has 32 points in 32 games, and Kempe has 31.
Kevin Fiala scored midway through the third period on a blast from the left point, but the goal was wiped out because of goaltender interference by Moore.
Moore made up for it by scoring with 1:59 remaining. It was his 17th of the season.
Up next for the Kings: vs. Edmonton at Crypto.com Arena on Saturday.