NFL-- The only significant obstacle facing the Justin Fields-led Bears offence, Per 49ers DC DeMeco Ryans.

In the first week of the 2018 season, the San Francisco 49ers will face a crucial test.

They will be competing against the Chicago Bears pass offence, which is led by Justin Fields.

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DeMeco Ryans, the defensive coordinator for the 49ers, game-planned against Fields last year, and his defence had mixed success.

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While Fields was limited to fewer than 200 passing yards in the Week 8 contest, the 49ers still emerged with a double-digit victory.

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On the ground, the former Ohio State standout proves to be too much for their front seven.

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Demeco Ryans amassed 103 rushing yards, a career high, and one rushing touchdown.

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Fields will be Ryans' opponent for the second straight season as Ryans continues to get his defence ready.

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Ryan is quite concerned about what the dual-threat quarterback can accomplish on the ground.

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Despite having a few small injury worries going into this game, the 49ers will at least have players like Nick Bosa and Fred Warner ready to help contain Fields and the Bears' revamped attack in Week 1.

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