NFL·Super Bowl LIV

49ers' stingy pass defence in for tough test vs. Patrick Mahomes

Led by a fearsome front four and lockdown cornerback Richard Sherman, the San Francisco 49ers had the NFL's stingiest pass defence in a decade this season. But shutting down Patrick Mahomes and Kansas City's passing game in the Super Bowl will be a huge challenge.

Chiefs QB led TD drives on all 5 first-half possessions in Week 3 win over San Fran

Chiefs quarterback Patrick Mahomes, who has scrambled 10 times for 112 yards in this year’s playoffs, leads the NFL with 76 completions the past two seasons on throws at least 20 yards downfield. (David Eulitt/Getty Images/File)

With a fearsome front four capable of pressuring quarterbacks without blitzes, a lockdown cornerback in Richard Sherman and the speed at linebacker and safety to limit big plays, the San Francisco 49ers had the league's stingiest pass defence in a decade.

Shutting down Patrick Mahomes and the Kansas City Chiefs' passing game in the Super Bowl will be a far tougher challenge than anything the Niners have faced this season.

"His mobility is unique. His arm strength is ridiculous. He's very, very accurate," defensive co-ordinator Robert Saleh said from Santa Clara, Calif. "But what I don't think people give him enough credit for is that he actually plays quarterback. There's a lot of people, there's a lot of quarterbacks in this league that will say no to number one and then it just becomes street ball. He gets rid of the ball on time.

He puts it where it needs to be. He hits a lot of throws in rhythm. And when he needs to take his shot, he knows how to buy time in the pocket and do it. So he's a superstar in every way you can possibly imagine and he's going to be tough to deal with."

The 49ers had to deal with Mahomes already in his brief but brilliant career. Back in Week 3 of the 2018 season in Mahomes' first year as starter in Kansas City, he threw for 314 yards and three TDs and led touchdown drives on all five possessions in the first half of the Chiefs' 38-27 win.

That marked the only time in the past 20 seasons that the Niners allowed five straight TD drives to open a game. They had no answer for Mahomes' play-making ability.

In the rematch next Sunday in the Super Bowl in Miami, San Francisco should be better equipped at least to try to slow Mahomes down.

Newcomers helped create turnovers

It added a dynamic edge rushing duo in the off-season, acquiring Dee Ford in a trade with the Chiefs and drafting Nick Bosa second overall. That led to the team allowing the fewest yards in a season since the 2009 New York Jets.

"When you have edge rushers it speeds up the process of the quarterback, and, not that he needs speeding up, he already gets rid of it pretty quick. But it changes the game," Saleh said. "It unlocks the offensive line so it creates a little bit more space and it gives the guys inside more space to operate. So having those guys out there, having them at full speed, will do nothing but help."

Bosa and Ford transformed the entire defence as the added pressure helped San Francisco create more turnovers after having a record-low seven takeaways in 2018.

The Niners have 57 sacks including the playoffs, with Ford, Bosa, Arik Armstead and DeForest Buckner all recording at least 7 1/2, making it difficult for offences to key on one spot.

"If we're covering and that guy takes two or three hitches most likely he'll be laying on his back," safety Jimmie Ward said. "But Patrick Mahomes is a mover in the pocket. I'm pretty sure he'll make some guys miss and he'll make some plays. We just have to make more plays than he does."

San Francisco got a league-best 40 of those sacks without bringing in extra pass rushers, which will be especially important against Mahomes, who has 22 TD passes, zero interceptions and a 118.3 passer rating in his career when defences rush five or more players.

But not getting pressure with four creates its own problems, giving Mahomes the extra times he needs to generate big plays downfield to speedsters like Tyreek Hill, Mecole Hardman and Sammy Watkins.

'We believe in each other'

Mahomes leads the NFL with 76 completions the past two seasons on throws at least 20 yards downfield, an aspect San Francisco's defence is designed to stop.

It allowed the second fewest deep completions in the regular season, with only eight on 48 attempts, thanks in large part to Sherman's coverage skills and Ward's ability as a free safety to cover ground deep downfield.

"We believe in each other," Sherman said. "We believe in the scheme. We believe in what we've done all year, and we plan on going out there and putting a good product on tape and seeing how it goes."

When San Francisco has struggled defensively this season it has often come against more mobile quarterbacks, with Kyler Murray, Russell Wilson and Lamar Jackson all having more success than QBs less apt to run like Aaron Rodgers and Kirk Cousins.

That's just another reason why Mahomes is so tough. He has scrambled 10 times this post-season for 112 yards, taking advantage of undisciplined rush lanes and defensive backs who drop too deep into coverage.

The quarterback who exploited that the most against the Niners this season was Wilson, who scrambled 12 times for 79 yards in two games, compared with just 20 scrambles for 82 yards against San Francisco in the other 16 games.

"Every week, whether you're playing a guy like Mahomes or a statue, it doesn't matter," Saleh said. "You have to have respect for where he is in the pocket. And your pass rush has to tie in with one another so that way you're just not carelessly rushing the passer to where even a statue can buy time and escape the pocket and create an explosive play through an off-schedule play. But that goes every single week."