Can the Niners emerge from the NFC with 'Mr. Irrelevant' at quarterback?

Brock Purdy can accomplish two things in the next several weeks: Shine as the incumbent "Mr. Irrelevant" and lead the 49ers to the Super Bowl.

Trying to win games will drive and consume him, but the first challenge will make the second more interesting. Injuries to Trey Lance in September and Jimmy Garoppolo on Sunday elevated Purdy, San Francisco's rookie third-string quarterback, to the starting role after being drafted last overall in April with the No. 262 pick.

To spark a playoff run, Purdy has to avoid undermining the 8-4 Niners' mighty defense, which he managed to do when he relieved Garoppolo last weekend. He threw two touchdowns and teed up Robbie Gould for three field goals to beat the Dolphins 33-17.

The spotlight beamed on Purdy, which was late 49ers receiver Paul Salata's goal when he coined the "Mr. Irrelevant" endearment in the 1970s.

"He wanted to randomly do something nice for someone," Salata's daughter Melanie Salata Fitch once told ESPN. "He had played football and thought: Let's honor the last guy (in the draft). Let's have that be our random guy."

Few last overall picks stick in the NFL for long, but a handful have won Super Bowls. Linebacker Marty Moore and fullback Jim Finn combined to play more than 200 games and were part of title teams with the Patriots and Giants, respectively, in the 2000s. Tampa Bay kicker Ryan Succop, the last man taken in the 2009 draft, ranks 30th all-time in made field goals and earned a ring with the 2020 Buccaneers.

Other Mr. Irrelevants have been in the news lately. Quarterback Chad Kelly took a knee on his lone NFL snap but starred as an injury replacement in November's Canadian Football League title game, spearheading the fourth-quarter TD drive that won the Toronto Argonauts the Grey Cup. Giants linebacker Tae Crowder's stock has slipped in his third season - he played zero defensive snaps last week and was exasperated postgame.

San Francisco won't sideline Purdy anytime soon, with Lance's broken ankle ruling him out for the season. Garoppolo is expected back from his broken foot in seven weeks at the earliest. That leaves the door open for him to return in the NFC Championship Game on Jan. 29 if the Niners avoid elimination.

A four-year starter at Iowa State, Purdy was the ninth QB drafted in a lackluster 2022 class and secured his roster spot by outplaying seven-year vet Nate Sudfeld in the preseason.

Unleashed in garbage time in Week 7, Purdy hit on four of nine passes for 66 yards and was intercepted in the end zone as the 49ers fell to the Chiefs. Pressed into action against Miami when Garoppolo's left foot was squashed mid-sack, he passed for a pair of scores from three yards out to make up for the pick he lobbed downfield on fourth down.

Purdy's simple approach and modest production did the trick. He released the ball in a tidy 2.48 seconds, the sixth-fastest rate among Week 13 starters, according to PFF. Seventeen of his 25 completions went for fewer than 10 yards. Purdy's average depth of target for the season (6.4 yards) ranks second-last among QBs with at least 50 dropbacks, but Garoppolo's ADOT (7.3) isn't substantially higher.

Garoppolo only threw for 300 yards once this year, clearing the benchmark in the blowout loss to Kansas City. But he wins because he takes care of the pigskin - he wasn't intercepted in San Francisco's ongoing five-game win streak - and the 49ers' pass attack is literally hard to stop.

Thanks to Deebo Samuel, Christian McCaffrey, and George Kittle, the 49ers lead the league in yards gained after the catch (6.6 per completion). Coach Kyle Shanahan's offense is replete with playmakers: Brandon Aiyuk ranks 22nd among NFL wideouts in total receiving yardage, Kittle is sixth among tight ends, McCaffrey is second among running backs, and Kyle Juszczyk tops all fullbacks.

Purdy won't be counted on to move mountains, but he has to be functional and protect the ball. The 49ers, who rank fourth in average time of possession, believe in him. Teammates praised Purdy's confidence and savviness under center in postgame interviews last week and talked up the experience he's gained in practice as the scout-team QB.

"He's played against the best defense in the league for the past 13 weeks," Niners middle linebacker Fred Warner told reporters. "He's gonna be just fine."

Warner's right about the defense he helms. The Niners lead the NFL in points allowed (15.8 per game) and yards permitted (283.9) and have held three opponents without an offensive touchdown. They rank sixth in sacks despite being 22nd in blitz frequency. No other team has unnerved Tua Tagovailoa, who's put up an MVP-caliber performance for the Dolphins outside of his three-turnover dud at Levi's Stadium.

Defensive coordinator DeMeco Ryans gets to work with stars. Destructive edge rusher Nick Bosa tops the NFL in sacks (14.5). Warner and linebacker Dre Greenlaw own top-10 PFF player grades at their position. Warner, cornerback Charvarius Ward, and rookie safety Talanoa Hufanga have combined to defend 26 passes, and Hufanga's four interceptions rank fourth league-wide.

San Francisco's defense ranks second and its offense is eighth in expected points added per play, according to Ben Baldwin's database. Only the Eagles and Cowboys are as good and complete as the 49ers in the NFC. Football Outsiders' playoff odds calculator gives them a 78.6% chance to hold off the Seahawks and win the NFC West.

The current playoff rundown favors the Niners. If the standings stay the same, they'd host the Giants - whose underlying numbers are poor - on Wild Card Weekend. They'll avoid the Cowboys in the first round, provided the Buccaneers, San Francisco's opponent on Sunday, don't catch fire.

Philadelphia and Dallas might be forced to clash in the divisional round, leaving San Francisco to face Minnesota, another apparent pretender that's racked up nine one-possession wins. By point differential and DVOA, the Vikings are the worst 10-2 club of all time by a wide margin, Aaron Schatz wrote at Football Outsiders this week. They rank 21st in points against and are 24th in DVOA against the pass.

Purdy could evade the NFC's best defenses until the conference title game, by which point he'd either be in a groove or backing up Garoppolo again. The scenario is optimistic but foreseeable. The Eagles and Cowboys are superb, but unheralded passers have won in January before.

When Phil Simms broke his foot late in the 1990 season, veteran reserve Jeff Hostetler drew in for the Giants and helped deliver a championship. New York's defense was the stingiest in football, while Hostetler wasn't intercepted in five appearances and peaked in the Super Bowl, hitting season highs in completions (20) and passing yardage (222) to defeat the Bills in the "Wide Right" game.

A decade later, Baltimore QB Trent Dilfer completed 47.9% of his pass attempts in the 2000 playoffs, accounting for less than 150 yards per game but only throwing one postseason pick. The fabled Ravens defense, anchored by Ray Lewis, allowed 10.3 points per game in the regular season, then conceded one TD across four playoff victories.

Backup QBs around the league face pressure this week. Tyler Huntley will aim to keep Baltimore afloat with Lamar Jackson injured, just as Cooper Rush steadied Dallas back when Dak Prescott was out. Erratic against the Vikings last week, Mike White still represents an upgrade from Zach Wilson for the Jets. Taylor Heinecke is similarly mediocre to Carson Wentz, but the Commanders happen to be 5-1-1 when Heinecke starts.

Like the Cowboys and Jets, the 49ers can stonewall opponents. Fielding a defense that dominates is a blessing - it boosts hope that a team will stay relevant deep into January.

Nick Faris is a features writer at theScore.