The San Francisco 49ers were upset by the Chicago Bears in Week 1, losing 19-10 to fall to 0-1 on the season.
In a game marred by severe rain, especially in the fourth quarter, neither team could really establish an offensive rhythm, with the 49ers consistently beating themselves with penalties and turnovers.
Here are the defensive grades for the 49ers:
Defensive Line: B
The 49ers were able to get consistent pressure on quarterback Justin Fields on Sunday, with the team racking up 12 overall pressures, however; they struggled to bring him to the group, missing tackles as the second-year player's elusiveness allowed him to extend plays.
Samson Ebukam led the 49ers with four pressures, while Nick Bosa recorded three pressures, and Javon Kinlaw and Arik Armstead had two a piece.
Charles Omenihu, Drake Jackson, and Kerry Hyder, who recorded 12, six, and four pass-rushing reps respectively, did not have a single pressure in the game.
Omenihu and Jackson were seen prominently as a part of San Francisco's third-down unit, with the former sliding to the inside, while the latter was opposite of Nick Bosa on the edge.
Despite the group not being able to contain Justin Fields inside the pocket at times, it was still a good performance overall for the unit that recorded two sacks, as Samson Ebukam and Nick Bosa each got to the quarterback once.
However, the overall grade gets knocked due to a Javon Kinlaw holding penalty that extended a Bears' drive in the redzone, setting up a 1st & Goal at the 3-yard line instead of a 3rd & 6. The Bears would eventually score the touchdown, increasing their lead to 19-10, making it a two-score game.
Linebackers: B-
Fred Warner was arguably San Francisco's best defensive player in Week 1, but the linebackers deserve just a B- overall grade in my eyes.
Warner was second on the team with six tackles, while playing solid coverage that limited the Chicago passing attack over the middle.
However, the other two linebackers, Dre Greenlaw and Azeez Al-Shaair, had crucial mistakes that led to scoring opportunities for the Bears.
Greenlaw had two personal foul penalties, with the second one being an unnecessary face mask call on third down that gave the Bears a first down on a drive that resulted in their first touchdown.
On Chicago's ensuing drive, Azeez Al-Shaair committed an unnecessary roughness penalty on yet another failed third down conversion, positioning the Bears deep into San Francisco territory before they scored their second straight touchdown.
Had those penalties not occurred, the Bears likely would've found it harder to score offensively, which would've potentially led to a 49ers win.
Cornerbacks: B+
Charvarius Ward and Emmanuel Moseley were lockdown cornerbacks for the most part on Sunday, with the former not allowing a catch on three targets, while the latter allowed only one catch for eight yards.
In fact, they were the primary reason that Justin Fields completed only 8/17 passes, with his two touchdown passes coming off broken plays.
Samuel Womack wasn't as great as his preseason performance indicated in Week 1, allowing a 22-yard catch while losing his responsibility near the line of scrimmage, being out of place.
Womack, though, was utilized on cornerback blitzes twice, and could be well-suited for the role with his traits, despite coming up blank in Week 1.
Ward did allow a costly holding penalty on 3rd & 9, extending the drive in which Azeez Al-Shaair later committed a personal foul, with both penalties coming on third downs. That drive ended in a Bears touchdown, giving them a 13-7 lead.
But, it was a promising start for the 49ers' cornerback duo on the outside, who were fairly good in coverage and will look to repeat their performances against the Seahawks in Week 2.
Safeties: B+
Talanoa Hufanga was another player who had a strong performance on Sunday, recording a team-high 11 tackles, including two tackles for loss, and an interception.
Hufanga looked especially good in the first half, as he consistently fit well in the run game, while playing the robber role well over the middle of the field.
However, Hufanga did have a lapse in coverage, leaving Dante Pettis wide open when Justin Fields scrambled out of the pocket, allowing the quarterback to find his receiver for an easy catch and a 51-yard touchdown that put the Bears on the board.
Later in the game, during Chicago's second touchdown, Hufanga rotated late as the single-high safety to a streaking Equanimeous St. Brown, which was the second touchdown of the game for the Bears.
Tashaun Gipson had his ups and downs in Week 1, playing in his first game as a 49er after being elevated from the practice squad. Gipson started over special-teams standout George Odum at safety, despite his minimal experience with the team, as the former played 98% of the defensive snaps, while the latter played 0% of the defensive snaps.
Overall, the defense played well, but lapses and certain penalties led to the Bears scoring 19 points, which was ultimately enough to defeat the 49ers in Week 1.