EL SEGUNDO, Calif. — Despite all the tough losses, all the injuries throughout the season, the Los Angeles Lakers reminded everyone Monday of a very important truth: They can still beat the NBA’s best teams.

The Oklahoma City Thunder entered Crypto.com Arena with the best record in the Western Conference but left with a humbling 116-104 loss.

Defense did it for the Lakers, who were in the throes of a brutal stretch of the schedule but held Oklahoma City to 39% shooting and shut down NBA MVP candidate Shai Gilgeous-Alexander.

The Lakers’ coaching staff talked about the importance of defense at the team’s morning shoot-around. Stop the ball on defense, they implored players. Don’t gamble. Defend without fouling. Get defensive rebounds.

The Lakers pretty much did all of the above against the Thunder (42-19). Gilgeous-Alexander was the league’s second-leading scorer (31.2 points a game) but was held to 20 points on five-for-13 shooting. Jalin Williams, another blossoming star for the Thunder, made only two of nine shots for seven points.

“Our defense, man, kudos to our guys,” Lakers coach Darvin Ham said.

The Lakers had a near-flawless first half on defense, holding Oklahoma City to 30.6% shooting on the way to a 52-43 lead. It could have been better for the Lakers, but 12 first-half turnovers gave the Thunder way too many easy points (14).

“I told them at halftime it was like the best defensive half I’ve seen all season,” Ham said.

The Lakers extended their lead to 89-72 through three quarters thanks to a suffocating defense that hadn’t presented itself often this season.

D’Angelo Russell drilled back-to-back-to-back three-pointers early in the fourth quarter and the rout was officially on as the Lakers led by 24.

Russell was asked afterward if he liked having the hot hand.

“Hell yeah,” he told Spectrum SportsNet. “It seems like that’s what I do. Feels good. My teammates find me when I’m hot. It makes it easy when I stretch the floor like that. That’s what shooting does. It’s my pleasure.”

Something to file away in case the Lakers and Thunder meet in the playoffs: The Lakers finished 3-1 against Oklahoma City this season.

Something else that would please the ninth-place Lakers (34-29), even those that claim to ignore the standings: They pulled within two games of sixth-place Phoenix. The top six teams in the West get automatic playoff bids while teams seven through 10 take part in the always risky play-in tournament.

Anthony Davis had 24 points and 12 rebounds for the Lakers, who beat Oklahoma City in points in the paint, 48-36.

“We understand that when the ball is popping and everybody is feeling comfortable, we’ve been playing some really good basketball offensively,” said LeBron James, who scored 19 points.

The Lakers easily won the battle of the boards, 55-38.

The team continues a rough part of the schedule with home games Wednesday against Sacramento, Friday against Milwaukee and Sunday against Minnesota.