No journey to the Super Bowl is ever linear. Ever since the Miami Dolphins achieved football perfection in 1972, every team that has climbed the mountain has had to experience some kind of bump in the road, and any team that harbours ambitions of adding their name to the list must show an ability to win in different ways and prevail when one side of the ball misfires.

The 2022 San Francisco 49ers have hit several bumps in the road. From a Week 1 loss to the Chicago Bears in a monsoon, to losing the anointed quarterback of the future, Trey Lance, to a season-ending ankle injury in Week 2 and suffering back-to-back losses to the Atlanta Falcons and the Kansas City Chiefs, the latter of which saw them ship 44 points, there have been plenty of points this season where belief in the 49ers as the Super Bowl contenders has been tested.

But San Francisco's response to the blowout Week 7 loss to the Chiefs has been emphatic and has reaffirmed the 49ers' status as a heavyweight in the NFC.

The 49ers have reeled off four successive victories to surge to 7-4 and, if the season ended today, would win the NFC West and enter the playoffs as an extremely dangerous third seed.

Two of those four wins have been blowouts, San Francisco marrying devastating offense from a group overflowing with playmakers following the October trade for Christian McCaffrey with tremendous defensive fortitude to destroy a pair of NFC West rivals in the Los Angeles Rams and Arizona Cardinals on the road.

Even with the level of star talent they have at their disposal, the 49ers' offense has not been consistent. A continuing theme of their recent dominance has been DeMeco Ryans' defense, which reached its 2022 zenith to this point on Sunday with a shutout 13-0 win over the New Orleans Saints.

It was a performance that served as an encapsulation of why Ryans is likely to be the premier head coaching candidate this offseason and one that should serve to raise the question of whether his defense is one that could be among the select few that carries its team to Super Bowl glory.

The numbers point heavily to the 49er defense being of that standard.

San Francisco's shutout was the Niners' first since they beat Washington 9-0 in the 2019 season, and it was the first suffered by the Saints since Week 17 of the 2001 season. The 49ers were the team to dole out the shutout on that occasion in a 38-0 win.

While it was a 20-year low point for the Saints on offense, for the 49ers it was a continuation of an eye-opening run of defensive obduracy. The Niners have now pitched four consecutive shutouts in the second half, also keeping the Rams, Los Angeles Chargers and Cardinals off the board in the final two quarters. Achieving the feat for four quarters against the Saints, they have now not conceded a point in over 94 minutes of game action.

The 49ers' refusal to let the Saints avoid drawing a blank was made more amazing by the fact New Orleans had six plays from inside San Francisco's five-yard line, and the season-long defensive numbers for the Niners paint the picture of the defiance shown by Ryans' group that could well come to define their season.

San Francisco's defense ranks first in points per game allowed, yards per game allowed, rush yards per game allowed, yards per rush allowed, first downs per game allowed and passing touchdowns allowed.

Simply put, this is a defense that can shut down anything an opposing offense does well, and it has multiple means by which it can do so.

The 49ers have the sixth-highest sack rate in the NFL at 7.9 per cent but have a blitz rate of 28.7 per cent that is below the league average of 30.8 per cent, those numbers speaking to San Francisco's long-established ability to get home by only sending four pass rushers from their exceptionally deep defensive line.

Nick Bosa, the star of that front, recorded the fourth-down sack that essentially ensured the Saints would not score in Week 12, taking his tally for the year to 11.5.

Bosa is the fifth player since 2000 to record at least one sack in nine of his first 10 games of a season, joining Hugh Douglas (2000), Everson Griffen (2017), Robert Mathis (2005) and Demarcus Ware (2008).

Yet the Niners have also made a habit of sending successful blitzes at the right time, with linebacker Fred Warner and safety Talanoa Hufanga – who each forced fumbles on Sunday – proving adept at generating pressure when rushing from the second level of the defense.

Hufanga's physicality jarred a fumble from Alvin Kamara at the one-yard line in the first of two fourth-quarter red zone stops against New Orleans, the former fifth-round pick emerging as a star in a secondary that has duplicity to frustrate teams with precise and disciplined zone coverage and facilitate blitzes by succeeding when it pivots to man coverage, with cornerback Charvarius Ward, the 49ers' headline free agency acquisition, excelling in both areas.

As with many defenses around the NFL, the 49ers rely heavily on two-high safety zone coverages; however, they have used Cover 1 man on 13.35 per cent of defensive snaps, well above the league average of 10.64 per cent. When using that coverage, they have given up 5.22 yards per play, over a yard fewer than the league average of 6.58.

In essence, the personnel Ryans has at his disposal allows him to easily switch between the staple of a four-man rush with zone coverage behind it and a more aggressive approach at any point and still have complete confidence his defense will deliver.

Though blitzes are not an overly common feature of the game plan, San Francisco's underpinning defensive philosophy is all about aggression, which is evident throughout when Ryans' players are on the field, their relentless pursuit of the football critical to the 49ers' incredible success against the run – opponents have gained only 3.1 yards per play on the ground versus San Francisco – and game-sealing turnovers such as Kamara's goal-line fumble.

That defensive violence ensured San Francisco did not follow the 49ers' offensive fireshow against the Cardinals in Mexico City with a letdown even as that attack sputtered in comparison to its efforts at Estadio Azteca.

Fast, physical, disciplined and diverse with the players at every level to consistently dominate, the 2022 49ers defense has all the ingredients of a championship unit and proved it can carry the load in ensuring San Francisco won in a very different way in Week 12 following the blowout of Week 11.

With Jimmy Garoppolo playing some of the best football of his career, after sticking around to back up Lance in a prescient move by both player and franchise, and blessed with a skill-position group that features McCaffrey, Deebo Samuel, Brandon Aiyuk and George Kittle, the hope will be the defense will not have to shoulder the burden on a regular basis. But this four-game stretch has proven unequivocally that it can do so, and that is an excellent insurance policy for the 49ers as they plot a path to a second Super Bowl appearance in four seasons.