WHEN THE EAGLES RUN THE BALL: LeSean McCoy made it clear on Wednesday that he wants to "put the offense on my back," a claim that came after carrying the ball only eight times last week and watching the Bears' No. 32 rush defense on film. Expect McCoy to carry the ball often, and to be productive doing so. McCoy needs 170 rushing yards to break Wilbert Montgomery's single-season record from 1979, and it's not out of the question that gets there this week. That's a lofty goal, but the Bears allow 152.4 rushing yards per game and have allowed more than 170 total rushing yards in five games this season. Nick Foles is bound to get some yards, and Chicago has struggled at times with quarterbacks running. But McCoy will be the central figure in the offense. Tight end Brent Celek will be valuable as a run blocker.
The Bears were pleased with the progress last week when they held Cleveland to 93 rushing yards, and the return of linebacker Lance Briggs would be a big help. Briggs has been absent for two months and has been cleared to play against the Eagles. The Bears replaced retired Pro Bowler Brian Urlacher at middle linebacker with rookie Jon Bostic. One player who can help the Bears is Jay Ratliff, who will play his fourth game for Chicago at defensive tackle on Sunday and could be a big help to the run defense.
WHEN THE EAGLES PASS THE BALL: Nick Foles threw for a career-high 428 yards last week, although coach Chip Kelly admitted that Foles was "inconsistent" in the game. That's a testament to how well he's been playing, and Foles fine-tuned his mechanics this week. The key for Foles will be to avoid interceptions. His only two of the season have come in the past two weeks.
The Bears enter the game with the No. 11 pass defense in the NFL and have 17 interceptions this season, including two last week. They allowed 300 passing yards just once this season.
Foles connected with DeSean Jackson 10 times last week, but that will be more difficult to do against Chicago's secondary. Jackson is 135 yards away from breaking Mike Quick's single-season record set in 1983. Chicago did a solid job covering Dallas' Dez Bryant and Cleveland's Josh Gordon during the past two weeks. Riley Cooper remains a reliable target for Foles, but pay attention to rookie tight end Zach Ertz, who continues to improve each week. The Bears allow the fourth most receptions to tight ends in the NFL, and opposing tight ends have 12 receptions of more than 20 yards against the Bears defense this season.
The Bears will continue to miss Charles Tillman, although Tim Jennings and Zack Bowman have been played well. Defensive end Julius Peppers leads Chicago with 6.5 sacks, and Jason Peters will be tasked with blocking him on Foles' blind side.
WHEN THE BEARS RUN THE BALL: Bears running back Matt Forte trails only LeSean McCoy and Adrian Peterson with 1,200 yards this season, including three consecutive weeks with more than 100 yards. The Eagles have the No. 16 rush defense in the NFL and have gone three consecutive weeks without facing the opponent's top rusher. Forte will be a major test for defensive coordinator Bill Davis' unit, which has played well this season.
An improved offensive line has helped Forte. Left tackle Jermon Bushrod and left guard Matt Slauson were veteran free agent signees who have stabilized that side of the line. They average more than five yards per carry running behind both players. Their most rushing plays and yards are behind first-round pick Kyle Long, who played for Chip Kelly at Oregon. Chicago averages 6.16 yards per carry behind Long on 63 rushing plays. The Eagles allow only 3.67 yards per carry in that area. Cedric Thornton and Bennie Logan will need to have a strong game on the line, with DeMeco Ryans and Mychal Kendricks roaming the middle.
The Bears' No. 2 running back is Michael Bush, who has only 54 carries this season. Quarterback Jay Cutler seldom tucks the ball to run.
WHEN THE BEARS PASS THE BALL: This might be the Eagles' toughest test of the season, with the Eagles' No. 31 pass defense trying to limit Chicago's No. 5 pass offense. Bears receivers Brandon Marshall (90 catches, 1,185 yards, 10 touchdowns) and Alshon Jeffery (80 catches, 1,265 yards, seven touchdowns) are two of the finest receivers in the league. Quarterback Jay Cutler has returned from injury and has a 63.4 percent completion percentage with 16 touchdowns in nine games. He threw for 265 yards and three touchdowns in his first game back last week.
Coach Marc Trestman is a sharp offensive mind that has helped Cutler this season and found ways to maximize his weapons. That's not just Marshall and Jeffrey, but also includes Matt Forte out of backfield, Martellus Bennett at tight end, and Earl Bennett in the slot. Martellus Bennett is a big challenge for the Eagles, who have played well against tight ends for most of the season.
Both Jeffrey and Marshall are physical targets that thrive with the ball in the air. It's a similar matchup to the one the Eagles faced against the Arizona Cardinals. The Eagles allowed touchdowns to both Arizona receivers, but they benefited from the officials allowing for a physical game. If that can happen again on Sunday, it will be a good sign for the Eagles. Cornerbacks Cary Williams and Bradley Fletcher were signed in part because of their size and physicality. They both need redemptive games after last week's debacle in Minnesota.
The Eagles will benefit from the return of safety Earl Wolff, who has missed four games. If he's not rusty, the rookie is an improvement at a position of weakness for the Eagles. Cornerback Brandon Boykin passed his concussion test and returns to slot.
Cutler has been prone to turnovers in his career and has 10 interceptions in nine games. The Eagles need to pressure Cutler and force turnovers, which they were able to do against Arizona. Linebackers Trent Cole and Connor Barwin lead the Eagles in sacks as edge rushers. Vinny Curry will be valuable on passing downs.
SPECIAL TEAMS: The Eagles have struggled on special teams in consecutive weeks. They allowed two return scores against Detroit, which was partly the byproduct of the field conditions. They refused to kick the ball to Minnesota returner Cordarrelle Patterson last week, allowing for favorable field position. Chicago features return specialist Devin Hester and they're in the top half of the league in both kickoff returns and punt returns. Hester has a punt return touchdown this season. There will be pressure on Eagles punter Donnie Jones to continue his strong play.
The Eagles will miss core special teams players Colt Anderson and Kurt Coleman, so there will be new faces on the unit. DeSean Jackson is always a threat on punt returns. Brad Smith had a 47-yard kickoff return last week, so pay attention to whether he plays a bigger role. Alex Henery hit three field goals last week and has not missed one since Nov. 10.
INTANGIBLES: Both teams are in playoff contention and will have eyes on earlier games. The Eagles have won three consecutive home games and will have an energized crowd on Sunday Night Football. Chicago is 3-4 on the road this season. The two teams have faced each other five of the past six seasons, with Chicago winning four of those games. But both teams have new coaching staffs and schemes, so those matchups might not be as much of an indication.