After six games with the Eagles, Sam Bradford has nearly an identical passer rating (80.0) to the one he had after 49 games with the Rams (79.3). It would be simple to rationalize his struggles this season as just more of the same from the quarterback.

But Bradford has actually been worse than he was during his first five years in the NFL. He is being intercepted at almost twice the rate (on 3.9 percent of his passes) as he was in St. Louis (2.2 percent).

Theories for the disparity abound. Has it been the layoff after Bradford tore his left anterior cruciate ligament twice? Is it mental? Mechanical? Is it the new offense? Or is there just not enough of a sample?

"I'm not really sure where I thought I would be six games in," Bradford said Thursday. "I think you have expectations. You want to come out, you want to play well, you want to play to the best of your abilities. But as far as trying to predict how the season is going to go and where you're going to be, especially coming off the injuries, I think that's hard to do.

"Would I have liked to be a little sharper? Absolutely. But at the same time I think I've done some things really well, and I'm just looking to improve each week."

His completion percentage (64.1 vs. 58.6), percentage of passes for touchdowns (3.9 vs. 3.4), and yards per attempt (6.8 vs. 6.3) are all up compared with his numbers in St. Louis. But those gains likely have more to do with the offense and the personnel than anything related to Bradford.

Mark Sanchez had even greater improvement in nine games with the Eagles last season compared with his five previous years with the New York Jets. He completed 64.1 percent of his passes (55.1 with the Jets), had a 4.5 touchdown percentage (3.6), and averaged 7.8 yards per attempt (6.5).

Sanchez's interception rate (3.6 percent), however, was nearly the same as it was with the Jets (3.7). The law of averages suggests Bradford will lower his interception rate as the season progresses.

But he has only 10 games to regress to the mean. While an argument could be made to bench Bradford for Sanchez, it is pointless at this stage. No. 1, Chip Kelly dismissed the notion. "Sam's our quarterback," he said Tuesday. And No. 2, the Eagles won their last two games in spite of Bradford.

Bradford made incremental progress if you compared the first three weeks with the next two, but he regressed against the Giants and tossed three unforced interceptions. A stout Panthers defense awaits on Sunday night. Sanchez, for the record, had his best game in terms of passer rating (102.5) in the Eagles' 45-21 win over Carolina last season.

The last time Bradford faced the Panthers was the last time he wore a Rams uniform in a regular-season game. It was almost exactly two years ago when he first tore the ACL in his left knee as he was tackled out of bounds.

He suffered the same injury in August 2014 and missed all of the following season. Bradford, Kelly, and offensive coordinator Pat Shurmur - Bradford's coordinator in St. Louis - all have said the return from the injuries hasn't been a factor.

"I don't see him favor his leg or think about his leg in terms of anything we're doing from a training standpoint or from a game standpoint," Kelly said.

But it is impossible to get inside Bradford's head. Many of his errant passes have been underthrown. Against the Giants last week, for instance, he short-armed an open Zach Ertz in the end zone and was intercepted, he short-hopped a pass to Jordan Matthews when he stepped up in the pocket, and even his touchdown pass to Riley Cooper was behind the receiver.

Kelly said that trying to guide passes rather than "letting it rip" was one reason a quarterback may have the habit of underthrowing receivers. Bradford said he thought, in his case, it was mechanical. He said he addressed the problem with quarterbacks coach Ryan Day last week.

"I'm not sure my weight transfer has been where it should be on a couple of the throws," Bradford said. "I'm not really sure that I've gotten to my front leg. I think that's why some of them have been short. So I spent a lot of time this week trying to get back to the fundamentals."

There have been overthrows and wide throws, as well. Every quarterback's accuracy decreases the farther he throws, but Bradford's numbers on intermediate to deep balls have been poor. He's completed only 26 of 73 passes (35.6 percent) beyond 10 yards, and eight of his nine interceptions have come at that distance.

For someone billed to have repetitive accuracy, Bradford hasn't displayed a consistent knack for throwing into tight windows. But there have been glimpses of the quarterback Kelly said he gambled on, which could imply that Bradford still needs time to get accustomed to the new scheme.

The zone-read has been all but abandoned, but Kelly's "package" plays started to seep back into the offense last week. Bradford connected with Ertz on three pop passes when he also had the post-snap option to hand off.

Bradford doesn't have the option to audible pre-snap, like he did in St. Louis, but package plays are built to counter a shifting defense. There's one less option because Bradford isn't a threat to run, but the plays are still difficult to defend if executed properly.

"I'm not sure if I've ever really done that," Bradford said of the package plays. "It's almost similar to the zone-read, except you're not pulling to run, you're pulling it to throw. So that was a little new to me, but I feel good with it."

Kelly had to know it would take time for Bradford to adjust. But the Eagles' commitment to the 27-year-old is only the rest of this season. There's still time to turn things around. But what if this is as good as it gets?

@Jeff_McLane