The Kansas City Chiefs have Patrick Mahomes, Travis Kelce, and Taylor Swift to fill up their newsfeeds heading into Super Bowl 58. But what do the San Francisco 49ers have? Well, they have the so-called Mr. Irrelevant in their starting quarterback, Brock Purdy.

Purdy has been a major talking point leading up to Super Bowl 58, and really, well before that, going back early in the regular season. So much has been questioned of the young 24-year-old and his abilities, even though he has numbers and recognition that suggest he will be viable for the MVP award. As we all know, his critics will be the first to point toward that talented 49ers roster that not only accounts for offense but defense as well.

If you really break this down, though, the reason why there is such an emphasis on Purdy, besides being one of the starting quarterbacks in the Super Bowl, is that his success is being linked to those who are seething for victory. Though he is just in his second season in the league, Purdy is an x-factor, a catalyst to a team in the 49ers, and, better yet, for head coach Kyle Shanahan who desperately needs a win in Super Bowl 58.

For the 49ers, it's about history, creating another Super Bowl winning team for the first time since 1994. It's also about maximizing this current 49ers team, who have still yet to reach their full potential by winning an NFL Championship. And for Shanahan, it's about overcoming a stigma of not being able to win the big games and blowing late leads and saving his career in the process. But Purdy may not be the quarterback to accomplish all of that, even if Shanahan has hitched his wagon to him… for now.

The magnitude of what Shanahan and the 49ers are asking Purdy to do is no small feat. Winning a Super Bowl is one thing and difficult enough, but building upon a historic franchise and, more or less, saving a head coach's career in the process is an entirely different thing. To do that, you would more than likely have to have the best quarterback on the field — which Shanahan won't have again in Super Bowl 58.

The 49ers and Kyle Shanahan won't have the best quarterback with Brock Purdy in Super Bowl 58

QBs Matt Ryan, Jimmy Garoppolo, Brock Purdy

This will now be the third time that Shanahan doesn't have the best quarterback in the Super Bowl in his three trips to the big game. That dates back even to when Shanahan was the offensive coordinator with the Falcons in Super Bowl 51. That was probably Shanahan's best shot, though. Falcons' quarterback Matt Ryan was just named MVP for that season, but he was facing The GOAT in Tom Brady. And we all know how that one ended, with 28-3 infamously living on.

Then, in Super Bowl 54, we seemingly saw Tom Brady's GOAT replacement in Patrick Mahomes, where the Chiefs quarterback, even with his own subpar game, was better than Jimmy Garoppolo that evening and his one touchdown to two interceptions. Mahomes had two picks of his own, but he also had two fourth-quarter touchdowns.

Super Bowl victories aren't always determined in favor of who the best quarterback on the field is. But it has certainly proved that way against Shanahan so far. On Super Bowl Sunday, it's clear who the better quarterback is, and with no disrespect, he doesn't play for the 49ers.

49ers and Kyle Shanahan can't rely on Brock Purdy in the second half, fourth quarter if game is close

The 49ers more or less got hit in the mouth in their first two playoff games where they needed to make comebacks in the fourth quarter to win both games. But can they survive that sort of play in Super Bowl 58?

The Chiefs are a team that doesn't necessarily let leads get away from them, especially in the postseason this year, and that's because of their superb defense. In both the Wild Card Round and the AFC Championship, they walked in with leads at the half and only surrendered one total score in the second half in those games. Against the Bills in the Divisional Round, they were down only three points in the first half, yet allowed Buffalo to score just once in the second half.

The 49ers have only scored 14 points in their two first halves this postseason, making them have to scratch and claw to win those games in the second half. That simply won't work against the Chiefs.

It's going to take all four quarters to beat the Chiefs, but the 49ers and Purdy are going to need to get started early if they want to walk out of Allegiant Stadium with the Lombardi Trophy. Because if the game is close in the fourth quarter, that's not when Brock Purdy is at his best.

In the fourth quarter within seven points, Purdy is 13-of-28 with a 46.4 completion percentage, throwing one touchdown to three interceptions with a 42.4 passer rating. If it's within the last two minutes of the half, his numbers do get better; however, throwing 30-for-56 with three total scores and one interception, with a completion percentage of 53.6 and a passer rating of 76.1, according to CBS Sports player stats.

The Chiefs are much better at surrendering points in the first half (10) so if Purdy and the 49ers want to win the game, that's where the majority of their points will most likely come from. The Chiefs allow just 6.5 points per game in the second half and 3.7 in the fourth quarter, per Team Rankings.

This is two top ranked defenses facing each other, meaning that that game could be close late. We all know who the better quarterback is late in the fourth, don't we?