WASHINGTON — There were many reasons why the Sixers suffered yet another loss in Washington, but the biggest is that they didn’t take the struggling Wizards very seriously.

The Sixers led by as many as 11 points in the first quarter, trailed by as many as 15 in the fourth, before making a too-late comeback in Thursday’s 119-113 loss to the Wizards in Capital One Arena.

In a very quiet locker room, the Sixers’ players admitted that their mental focus wasn’t where it needed to be.

“We came in too relaxed, didn’t take care of the ball, waited too long down the stretch trying to get the game back,” said point guard Ben Simmons, who had 17 points and 10 assists, but many were negated by seven turnovers.

Being too relaxed doesn’t show the greatest concern for an opponent.

“We have to have the mentality where we have to come in focused, no matter who we playing, regardless of the situation,” Simmons said.

The Sixers are now 15-7 as they resume action with weekend home games Saturday against Cleveland and Sunday against Toronto.

While they are 10-0 at home, the Sixers are just 5-7 on the road. Four of those losses came to teams that are under .500.

What made this loss even more pronounced is that the Wizards’ best player, Bradley Beal, had an off game. Beal, who was frequently guarded by Simmons, had 26 points, but shot just 7-for-24 from the field, and 1-for-4 from beyond the arc.

Still, his teammates, particularly rookie Rui Hachimura (27 points) and Davis Bertans (25 points), picked up the slack.

Washington is 7-13, apparently going nowhere, but played with a fire, especially after that early first-quarter deficit. It was a fire that left the Sixers after their early spurt.

“We were up in the first quarter and then we kind of relaxed in the second quarter and they got hot," said Joel Embiid, who had 26 points and 21 rebounds, but also committed eight turnovers. "Trying to get back in the game, it wasn’t enough.”

There goes that relaxing again.

Tobias Harris, who had a game-high 33 points, talked about a lack of focus. This usually comes when a team takes an opponent for granted.

“We should have been locked in more in the game,” Harris said. “We have to be mentally tough, just a little more focused and execute and make the right plays to expand the lead, and too many times we get too comfortable.”

The Sixers had two days off before the game, having last played during Monday’s 103-94 home win over Utah. So they can’t blame fatigue.

“I thought that it took us about 35 to 38 minutes to come with an energy that we have been playing with,” coach Brett Brown said. “You don’t attain defensive standards and ranking that we have, playing the way we did the first three periods.”

The Sixers dug too deep a hole, and when they finally did take the Wizards seriously, it was too late.