The previously undefeated San Francisco 49ers were beaten by an aggressive defensive play caller in Sunday's 19-17 loss to the Browns, and they're about to face another one in Vikings defensive coordinator Brian Flores on Monday night at U.S. Bank Stadium.

Flores doesn't have near the depth chart Cleveland's Jim Schwartz enjoys, including former Vikings defensive linemen Za'Darius Smith and Dalvin Tomlinson, along with one of the game's best edge rushers in Myles Garrett. And the Vikings could be without edge rusher Marcus Davenport for a while.

This means the Vikings will need a master class from Flores and their defensive front to come close to replicating Cleveland's success against San Francisco's offense.

The Vikings put the clamps on a much lesser foe in Sunday's 19-13 win in Chicago, where Bears quarterback Justin Fields was blitzed early and often. Minnesota forced a league-high pressure rate on Fields in Week 6, per Pro Football Focus, and knocked him out with a thumb injury during one of four sacks.

Behind another flurry of blitzes, the Vikings hit Fields on seven of his 14 passing plays in which he did not scramble. Safety Josh Metellus, linebacker Ivan Pace Jr., edge rusher D.J. Wonnum and defensive tackle Harrison Phillips each hit Fields, providing help for edge rusher Danielle Hunter as he attracted chips and double-teams in protection.

"It puts on film to let other people know that everybody on the defense can be put in position to make plays out there," Hunter said after the game.

In the video below, you'll see Metellus (No. 44) blitz off the edge. It's a six-man pressure that forces Fields to make a quick decision. Metellus tags Fields, who throws into the area vacated by Metellus. But sure tackling from linebacker Jordan Hicks (No. 58) stalls the 1-yard gain.

It's not easy to disrupt this efficient 49ers offense. Although quarterback Brock Purdy has a lesser but still solid passer rating — 101.6 — when blitzed compared to 119.6 when he's not, according to PFF. Not that Flores needed any encouragement; the Vikings have a league-high blitz rate of about 48%, per Pro Football Reference.

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Purdy was the fourth-most pressured passer last week.

After Purdy's first regular-season loss, 49ers head coach Kyle Shanahan told reporters his juggernaut offense was too often sent backward.

Cleveland was stout against the 49ers' vaunted run game. San Francisco was physically overpowered — and beaten up; running back Christian McCaffrey and receiver Deebo Samuel left the game because of injuries, while left tackle Trent Williams was reportedly seen in a walking boot postgame.

Yet the 49ers were still only a missed 41-yard field goal away from winning.

"We have two drives in that game that didn't have a negative play — that was the first drive when we scored a touchdown, and it was the last drive when we ended up missing that field goal," Shanahan said Monday. "We got into some negative situations where we had second-and-long and third-and-long. With that pass rush and the tight coverages, it makes it really tough on a quarterback."

The Browns don't have to be a blitz-happy team. But they flustered Purdy with extra rushers, including on a first down when San Francisco had a chance to salt away the game with a 17-16 lead late in the fourth quarter.

In the video below, you'll see the 49ers botch this Browns blitz by linebacker Jeremiah Owusu-Koramoah.

Shanahan blamed this on the design or protection decision to send running back Jordan Mason (No. 24) on a route, leaving Brandon Aiyuk (No. 11) covered initially when Mason's defender backpedaled into the throwing lane. But really, Purdy was turned and running from the unchecked pressure before he had much of a chance to throw.

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