HENDERSON, Nev. -- Las Vegas Raiders coach Klint Kubiak does not anticipate any changes to the defense, expressing confidence in first-time defensive coordinator Rob Leonard after their 38-17 loss to the 49ers on Sunday -- the sixth straight game of allowing 30-plus points.

"In fact, I see us doing the things we said we're going to do [but] better," Kubiak said Monday. "Stand behind, Rob. Stand behind our defensive staff. Stand behind our players. And I think the world wants someone's head on the platter every time things don't go right. But the way that I see it is that we brought people here for a reason: to get a job done and develop players for the long haul."

Leonard's time as the defensive playcaller started with promise before turning into a complete disaster. During the Raiders' 3-0 start, they were eighth in points allowed (18 points per game), 11th in total yards allowed (316.7), second in EPA (22.65), third in defensive efficiency (75.96) and first in opponents' QBR (27).

They were also tied for seventh in quarterback pressures (42), tied for fourth in sacks (10) and first in forced turnovers (9).

The Raiders have lost five of six games since their 3-0 start, and the defense is a big reason for their struggles. Since Week 4, Las Vegas is near the bottom in every statistical category. They are last in points allowed (35.7 per game), rushing yards allowed (168.7) and defensive efficiency (17.54). Las Vegas is 17th in pressures (63) and tied for 29th in sacks (9).

The Raiders have only recorded five turnovers during this stretch.

In Week 9, San Francisco picked apart the Raiders in the pass and run game. Las Vegas gave up 190 rushing yards, including 94 in the first quarter. They had difficulty creating pressure on quarterback Brock Purdy, who completed 17 of 25 passes for 232 yards, two touchdowns and an interception.

Las Vegas gave up 414 total yards while the 49ers had possession for 38 minutes and 18 seconds.

Despite the team's issues on defense, Kubiak still believes in the defensive scheme and the playcaller.

"I have seen it work. Just not for four quarters," Kubiak said. "... As a group, it's putting four quarters of football together no matter who's the opponent. You play a damn good offense in San Francisco; there's got to be a happy medium somewhere between the first half and second half."