CHICAGO -- The Bears have made a habit of being a thorn in the side of some of the NFL's best teams. Saturday was no different.
The Bears jumped out to an early 10-6 lead on the Buffalo Bills at frigid Soldier Field but were eventually undone by injuries, questionable play calling, and a lack of talent at key positions.
Quarterback Justin Fields was held in check by the Bills' defense, and Buffalo left chilly Chicago with a 35-13 win.
The Bears' offense lacked punch, and the defense was gashed on the ground by a Bills' rushing attack that has been inconsistent all season.
Here's a Christmas report card the Bears won't want to hang on the fridge.
Passing offense
The Bears' air attack barely got off the ground Saturday against the Bills.
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With starting guards Cody Whitehair and Teven Jenkins out with injuries, the Bears' offensive line struggled against Bills' defensive tackle Ed Oliver and the Bills' front four.
Fields and the passing game were crisp on the opening drive. The second-year quarterback found Byron Pringle for a 20-yard gain and then hit a wide-open Dante Pettis for a 6-yard touchdown.
Those would be the only fireworks for the Bears' passing attack. With Chase Claypool, Darnell Mooney, and Equanimeous St. Brown out, the Bears lacked playmakers needed to stress the Bills vertically.
A 44-yard catch by Velus Jones Jr. was the only highlight after the Bears' opening drive.
Grade: D+
Rushing offense
A ground game that usually is led by Fields was relatively quiet Saturday.
The Bills made a concerted effort to send pressure off the edge to force Fields to give up the ball on read plays. Buffalo did an excellent job of keeping Fields in the pocket so he couldn't get outside and use his elite athleticism to create game-changing plays.
David Montgomery led the Bears with 62 yards on 16 attempts (3.9 per carry). Khalil Herbert looked rusty in his return, rushing for just 7 yards on six carries.
With 2/5 of the offensive line, the Bears struggled to gain consistent traction in the run game.
Grade: D
Pass defense
The Bears started three rookie cornerbacks Saturday. On paper, that seemed like a matchup Bills quarterback Josh Allen and wide receiver Stefon Diggs should exploit.
The Bears' rookie trio had other plans.
Kyler Gordon, Jaylon Jones, and Josh Blackwell all acquitted themselves well against the vaunted Bills passing attack.
Allen completed just 15 of 26 passes for 172 yards and two touchdowns. He also threw two interceptions. Gordon held up well as the Bears' No. 1 corner, with Jaylon Johnson done for the season. The second-round pick helped hold Diggs to just two catches for 26 yards.
No Bills receiver topped 50 yards.
A good day from the pass defense was overshadowed by a horrific effort trying to stop the run.
Grade: B
Run defense
There was absolutely nothing redeemable about the Bears' run defense Saturday against the Bills.
The front four made little impact, the linebackers were nowhere to be seen, and the secondary took some truly brutal angles when trying to track down James Cook and Devin Singletary.
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The result?
The Bills rushed 254 yards (8.2 per attempt), including touchdown runs of 33 and 27 yards.
The Bears have struggled to stop the run all season, but Saturday might have been their worst effort to date.
Grade: F
Special teams
Richard Hightower's unit played pretty good football in blustery conditions Saturday.
Jones racked up 113 kickoff return yards, Cairo Santos went 2-for-2 on field goals and made his PAT, and Trenton Gill averaged 49.3 yards per punt and downed one of four inside the 20.
Solid Christmas Eve for special teams.
Grade: B