PHILADELPHIA (973espn.com) - Forget about fate being fickle, sometimes it can be downright cruel.

Jim Schwartz has been getting heat for a defensive unit which has performed poorly in big situations and collapsed too often down the stretch of losses.

A major part of that has been injuries to the defensive backfield and when the gun sounded on the Eagles' latest loss, a disappointing 27-20 setback to NFC East-rival Dallas on Sunday night, Schwartz was without four of his five projected starters on the back end -- cornerbacks Jalen Mills, Ronald Darby and Sidney Jones as well as safety Rodney McLeod.

Jones hopes to be back this week in New Orleans but Mills is likely still going to need some time while Darby and McLeod are done of the season and possibly their Philadelphia careers with significant knee injuries.

That means largely unproven players like Rasul Douglas, Avonte Maddox, Chandon Sullivan and perhaps Cre'Von LeBlanc will be tasked with helping to stop one of the best offenses in NFL history.

The 8-1 Saints have been unstoppable at times with unique playmakers like Alvin Kamara and Taysom Hill complementing obvious superstars like future Hall of Fame quarterback Drew Brees and perhaps the top receiver in football, the physically imposing Michael Thomas.

It all starts with Brees, who has turned defensive looks into glorified 7-on-7 drills, completing a mind-numbing 77.3 percent of his passes through nine games, shattering the best mark in league history at that stage of a season (73.2 by Tom Brady in 2007).

"I looked at his interception reel," defensive coordinator Jim Schwartz quipped, pointing to Brees' video-game-like 22:1 touchdown-to-interception ratio. "That was one. Didn't take us long to get through the sack [only 9 on the season] and interception reel. His incompletions, didn't take us long to get through those. I mean, he's playing at an insane level right now. It's sort of a trend of where the NFL is."

When Schwartz was a child he explained that a QB completing 50 percent of his passes who has a TD-to-INT ratio that was even was considered good. From there it became twice as many touchdowns to interceptions and a 60-percent completion rate. Now it's almost become Arena League numbers. No matter the expectation, though, Brees has shattered it with his 2018 season so far.

"Now pretty much everybody is like near that 70 percent. He's close to 80. He's 77 point something. How about 21-1 touchdown-interception? He's made those things the new standards," Schwartz said. "Extremely accurate quarterback, smart, knows where to go with the ball. Still has good mobility, can buy time. We certainly have our work cut out for him."

Thomas, meanwhile, has 78 receptions already and four 10-reception games while Kamara is perhaps the most dynamic dual-threat running back in the game.

"He's got good players around him. They're also, I think, maybe lost in the fact that he's played at such a high level," Schwartz said. "They're a very good run team also. [Saint RB] Mark] Ingram, Kamara, doesn't matter who they hand the ball off to, they've been a consistent run team. Very good offensive line. There is a reason that they're the No. 1 scoring offense in the NFL."

The lone positive for the Eagles may be the fact that the offensive tackle tandem of Terron Armstead and Ryan Ramczyk, which has been the best in football, will be a man down after Armstead, the left tackle, suffered a pec injury during a blowout in Cincinnati last week and will not be available.

The wild card to it all may be Hill, a matchup nightmare who serves as a zone-read QB who can double as a blocker, runner, receiver or tight end.

"I think the thing that's a little bit of a different challenge with Hill is he played quarterback, he plays running back, he plays tight end, he plays wide receiver," Schwartz explained. "He wears so many hats, that you have to cover him in all those aspects. Wildcat plays, read-option plays, those are nothing new. It's all the different things you have to be prepared for him lining up as a wide receiver. He can block like a fullback, he can block like a tight end. So it does give you a little bit more."

As a whole, the Saints have scored 331 points and average 15 points per game more than the Eagles. They've scored 40 points five times and are averaging 37.3 points-per-game at the Superdome.

“They're the hottest team in the NFL,” Douglas said. “Their offense is pretty good, I haven't seen anyone stop them on film yet. They've got a great quarterback in Drew Brees who can make all the throws. So, it's going to be a big test. We just need to be locked in and go down there ready to play.”

-John McMullen covers the Eagles and the NFL for 973espn.com. You can reach him at jmcmullen44@gmail.com or on Twitter @JFMcMullen