The Bears' defense presents a big test for the Eagles on Sunday, as I wrote on Thursday, but the Chicago offense comes with its own set of challenges as well. This group has undergone a huge face-lift from the unit that struggled to do much of anything here at Lincoln Financial Field last fall, as a change in scheme, the influx of playmakers, and another year of experience for their young talent have really paid dividends in 2018.

Let's start with the scheme, where this offense should look plenty familiar to Eagles fans. Not only is head coach Matt Nagy cut from the same cloth as Doug Pederson as a disciple of Andy Reid, but offensive coordinator Mark Helfrich worked under former Eagles head coach Chip Kelly during their time together at Oregon. In fact, Helfrich replaced Kelly as the head coach in Eugene when he left to come to Philadelphia. In both offenses, the RPO (Run Pass Option) is a staple and it's very prevalent in Chicago.

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The Eagles run plays like this every game. The quarterback has the ability to either hand the ball off or throw it, and it all depends on the "read defender." Whomever the offense decides to read on any given play – whether it's a lineman, a linebacker, or a defensive back, if that player decides to play the pass, the quarterback hands it off. If that read defender plays the run, the quarterback throws it. It's ultimately that simple for the offense, and it can be tough to stop for a defense to stop. For that reason, the Eagles have to make sure they all do their jobs. The moment any one defender tries to do more outside of his 1/11th, that creates trouble and the potential for a big offensive play.

Now let's look at the personnel in the backfield for Chicago, who dresses a handful of backs for every game. The two main ballcarriers, however, are Jordan Howard and Tarik Cohen. This "Thunder and Lightning" combo can create big plays between the tackles, typically with Howard, and outside the numbers, usually with Cohen, though both guys cross over at times as well.

Howard is a physical, instinctive runner who can churn out tough yards and be a factor in their various downhill schemes. The Eagles completely erased him in last season's matchup, holding Howard to 6 yards on seven carries. Granted it was a different scheme, but the Eagles will need a repeat effort on Sunday.

Cohen is the lightning rod, and he will be the X-factor for Chicago in this battle. He can execute those inside runs as well, but he's so effective out on the perimeter in the option run game. The Bears use him much like the Eagles utilize Darren Sproles on draw plays as well as in the screen game. As Greg Cosell noted this week on Eagles Game Plan, however, Cohen is a vertical weapon in the passing game as well, and they love getting him open down the field.

As Greg said, the Bears love using Cohen on the boundary side of the field (the short side). Why? Wouldn't you want him out in space? The answer is because on the boundary side, a lot of defenses play man coverage. Even when the defense is in zone coverage, teams will typically play straight man to the short side of the field, so the opportunity to get Cohen matched up on a linebacker or a safety on some kind of a rub route (like you see above) is increased. This will be a challenge that awaits the Eagles on Sunday.

Along the same lines, the Eagles must have a plan for Trey Burton as well. Eagles fans are well aware of what the versatile tight end can bring to the table, and he was a big part of the Bears' offense this year. Cohen led the team with 14 targets in the red zone, and Burton was right behind him with 13. He lines up everywhere – and wins. He made plays for the Bears at all three levels of the field this season. Who will match up to Burton in man coverage when Cohen is also on the field? This is a big question that must be answered, and I can't wait to see the Eagles' plan for this matchup.

The Bears have one of the top red zone offenses in football with versatile, dynamic weapons like Cohen and Burton. A lot of the success is also due to scheme. Chicago pulls out all the stops when it gets inside the 20-yard line. With the Bears, it's not just about the X's and O's, because the Jimmys and Joes are just as important. Any time the Bears get into that part of the field you have to be ready to see anyone ... even defenders playing offense.

Trick plays. Distracting decoys. Crazy personnel groupings. The Eagles have to be ready for anything from this Chicago offense down near the goal line.

The Bears completely overhauled their receiving corps this offseason, bringing in Burton to play tight end but also acquiring both Allen Robinson II and Taylor Gabriel in free agency while selecting Anthony Miller in the second round of April's draft. These weapons have given quarterback Mitch Trubisky more options in a more dynamic passing game.

There are a lot of targets in this passing game that the Eagles must match up to. It certainly presents a big challenge for the secondary. What is the answer? They must get to Trubisky. Don't give him time to find these weapons down the field. The Eagles have been able to dominate the line of scrimmage during this win streak, resulting in a ridiculous run defense. Running backs over the last three games against this Eagles defense have carried the ball 35 times for just 82 yards (2.3 yards per carry). If the Eagles can stop the run and get to Trubisky, that will play a huge role in a victory.

But getting to Trubisky is a bit trickier than you'd imagine. He's actually one of the better scrambling quarterbacks in the league this year, and his ability to get away from trouble for first downs has been frustrating for defenses all season long.

The Eagles have given up plays to quarterbacks running the football this season – Houston's Deshaun Watson ran for 49 yards, Jacksonville's Blake Bortles ran for 43, Carolina's Cam Newton ran for 49, Tennessee's Marcus Mariota ran for 46, and Indianapolis' Andrew Luck ran for 33. They can't allow Trubisky to escape in key situations, so being disciplined in their rushing lanes will be pivotal in this game.

Fran Duffy is the producer of the Emmy-nominatedEagles Game Planshow which can be seen every gameday during the season on NBC10 in Philadelphia. He is also the host of two Eagles-related podcasts,Eagle Eye in the Sky, which examines the team from an X's and O's angle each and every week as well as the Journey to the Draft podcast, which covers college football and the NFL Draft all year round. Fran also authors the Eagle Eye in the Sky column, which runs four times a week during the football season to serve as a recap for the previous game and to preview the upcoming matchup. Prior to joining the Eagles in 2011, Duffy was the head video coordinator for the Temple University football team under former head coach Al Golden. In that role, he spent thousands of hours shooting, logging, and assisting with the breakdown of the All-22 film from the team's games, practices, and opponents.