New York has lost nine straight road games since Nov. 1, getting outscored 38-14 during its longest road skid since 1998-99.
"I know what our record is, but it's not like we're getting dominated in these games," Islanders coach Jack Capuano said. "If we're not going to score any goals, it's going to be tough for us. We didn't generate (anything) on our power play, and that's probably the difference."
After a scoreless first period, Islanders captain John Tavares set up his teammates for a pair of fine scoring chances during second-period power plays, but Thomas Vanek and Brock Nelson both failed to capitalize. Josh Bailey missed his own chance, clanging a backhand off the crossbar on a near-breakaway.
Kopitar finally got the Kings on the board thanks to an exceptional long pass from Alec Martinez, who found his Slovenian teammate lightly marked at the far blue line. Kopitar slipped into the slot and used a slick move to score his eighth goal. The Kings' perennial leading scorer has 20 points in the last 22 games.
Brown added his sixth goal midway through the third period, capitalizing on confusion behind Poulin to gather the puck for an easy wraparound score. The Kings' captain is having a rough offensive season, but has scored goals in consecutive games for the first time since late March.
NOTES: New York dressed rookie C Nelson and scratched C Peter Regin, who had missed just one game all season. Regin is scoreless in his last 17 games. Poulin made his first start in a week after Anders Nilsson played the Isles' last three games. ... Los Angeles wore its purple-and-gold throwback jerseys on a "Legends Night" honoring Hall of Fame defenseman Larry Murphy, who set NHL records for most assists and points by a rookie defenseman with the Kings in 1981. ... The Kings open a four-game trip Tuesday in Montreal. ... New York has lost on the first two stops of its five-game West Coast road swing.