OAKLAND — The Raiders are a better team in 2015, and that has a lot to do with Derek Carr.

The Raiders aren’t a playoff team in 2015, and that has even more to do with Carr, who has in some ways regressed to his rookie level of play when the Raiders needed him most.

In a 30-20 loss to the Green Bay Packers on Sunday at O.co Coliseum, Carr spotted the Packers a 14-0 lead with a pair of interceptions, including an overthrow that Damarious Randall returned 43 yards for a touchdown.

The lengthy interception return has been a Carr specialty. He has been intercepted 11 times, three for touchdowns, at an average of 34.5 yards per pick. Interception No. 1 against Green Bay, an underthrown force intended for Clive Walford, was returned 34 yards to set up the Packers’ first touchdown.

Over the last three games, with the Raiders on the periphery of the playoff race, Carr completed just 53.2 percent of his passes (66 for 124) for 694 yards, six touchdowns and five interceptions. His rating of 69.1 in those games is lower than his rookie season mark of 76.6.

A team that has played pretty stout defense over the past three games has seen the offense score just seven touchdowns with four field goal attempts, five interceptions and 19 punts in 40 possessions.

Coach Jack Del Rio has no explanation.

“I can’t really tell you anything there,” Del Rio said. “I can just tell you he’s a good player. We have a bright future because of guys like him. We’re going to continue to grow with him and learn from the experiences that he’s getting.”

On only two possessions against the Packers did Carr look like the guy who earlier in the season appeared on the verge of being an upper-echelon quarterback. A 79-yard drive took just four plays and ended with a 19-yard touchdown pass to Amari Cooper to get the Raiders within 14-13.

Following a 24-yard Mason Crosby field goal, Carr drove the Raiders 81 yards in eight plays, hitting Cooper again for a 20-17 lead with 6:48 left in the third quarter.

Despite all that momentum, Carr and the offense failed to capitalize.

“We got it going a little, but then we weren’t able to sustain it when it was crunchtime,” Del Rio said.

Carr’s statistics coming in were remarkably similar to those of Packers quarterback Aaron Rodgers. Yet in Year 2 of his development, Carr more resembles a young Brett Favre and even wears his uniform number out of respect.

The young Favre was capable of placing gutsy throws into tight windows, mixing in other passes that had coach Mike Holmgren apoplectic and questioning the judgment of his quarterback.

Del Rio’s carousel of quarterbacks in Jacksonville were so mediocre that it’s remarkable he kept his job for eight-plus seasons. Carr is a considerable upgrade from anything Del Rio has ever had.

So when Carr threw the second of his two interceptions, it wasn’t as if Del Rio was looking for Matt McGloin to come to the rescue.

“I don’t think biting his head off right there is going to help him bounce back,” Del Rio said.

Said Carr: “It was just like, ‘things are going to happen, I believe in you.’ ”

The maddening thing about Carr is there are just too many instances of having to play through rough patches that are often the difference between winning and losing.

After falling behind 14-0, Carr twice got the Raiders into the red zone but couldn’t get a touchdown, having to settle for chip-shot field goals from Sebastian Janikowski.

Following the two touchdown drives, the Packers began getting a better pass rush. We’ve learned through 30 games that Carr has some mobility, but when it comes to throwing the ball, he needs to be set to deliver the ball properly.

Carr isn’t Rodgers or Ben Roethlisberger, with the ability to wing the ball off the back foot and turn a broken play into a big play. When Carr has the ball too long and is attempting to make something happen, the end result is usually bad.

His two touchdowns to Cooper served as an example of how he can be successful. On the first, he rolled to his right but planted and set his feet before delivering his 29th touchdown pass. On the next, it was a classic drop and throw, this time for 26 yards, for his 30th touchdown pass.

“I think he’s very accurate when he’s on balance and fundamentally doing things,” Del Rio said.

On the plus side, Carr did rush for a pair of first downs on scrambles, and it isn’t his fault that the Raiders came in with 34 dropped passes according to Profootballfocus.com and added another four or five against Green Bay.

Carr, the Raiders quarterback of the future, has done a lot.

And not enough.

For more on the Raiders, visit the Inside the Oakland Raiders blog at ibabuzz.com/oaklandraiders. Follow Jerry McDonald on Twitter at twitter.com/Jerrymcd.