Is Patrick Mahomes an Immediate Upgrade for the Kansas City Chiefs in Fantasy Football?

With Alex Smith being traded to Washington, Patrick Mahomes is set to start for the Kansas City Chiefs in 2018. What does this do to the fantasy football value of Travis Kelce, Tyreek Hill, and Kareem Hunt?

If you have had the pleasure of watching Patrick Mahomes play football either in college or in his rookie season with the Kansas City Chiefs, two things are abundantly obvious.

1. Lil dude can chuck a football.

2. This guy should not be riding a bench in the NFL.

It would seem the Chiefs have come to similar conclusions.

Mahomes has been freed. Let us rejoice and be glad.

Not many young quarterbacks get to jump right into a situation in which they'll be throwing to studs like Travis Kelce and Tyreek Hill while handing off to Kareem Hunt. The surroundings for Mahomes are ideal, and they should make us optimistic about his performance regardless of talent.

This obviously has huge implications for fantasy football. If Mahomes steps in and immediately improves the offense, it'll up the appeal around Kelce, Hill, and Hunt. Efficient quarterbacks generate more touchdown drives, and that means more fantasy goodness to go around. If he's the real deal, we need to be buying everyone in this offense, Mahomes included.

But is that a realistic expectation? Can we expect Mahomes to step in and perform better than what Alex Smith did in 2017? Let's take a deeper look at that question and try to see what we can learn about the fantasy values for those big three for 2018 and beyond.

Why the Question Is Flawed

The central question here is, "Is Mahomes an upgrade over Smith for 2018?" If yes, we should be getting as many Chiefs on our rosters as we can handle. If no, then we may need to proceed with caution.

Unfortunately, that question is a flawed one. We need to approach this from a different angle if we want to get the right answers.

Because we have limited data on Mahomes in the NFL (and that which we do have is from the preseason and Week 17, both of which were played without the team's best assets at his disposal), we're not going to know where his current talent lies relative to that of Smith. Additionally, comparing Mahomes to the 2017 Smith assumes the Chiefs were bound to repeat Smith's level of efficiency in 2018, and that is a mighty bold assumption.

In 2017, Smith finished eighth in the league in Passing Net Expected Points (NEP) per drop back out of 45 quarterbacks with at least 100 drop backs. NEP is the metric we use to track the expected points added (or subtracted) on each play, including deductions for negative plays such as sacks, interceptions, and incompletions. Because this looks at expected points rather than yardage, NEP is able to illustrate the immense difference between a three-yard completion on 3rd and 2 and that same completion on 3rd and 4.

Basically, Smith was really good last year. Outlierishly so. When you add in the expected points he added as a rusher, Smith had 133.95 Total NEP, the fifth-highest mark in the league. That wasn't just his first top-five finish in the NFL, but it was his first in the top 10 and only his third top-15 season. Smith played out of his gosh-darn mind, and it earned him a fat new contract.

Why does this matter for Mahomes and the Chiefs? Our valuation of Kelce, Hill, and Hunt is based on what they did in 2017. In that season, they were playing on an offense that was quarterbacked by one of the most efficient passers in the league, allowing them to finish with the sixth-most points of any team. In order for us to boost our valuation of the assets, we need Mahomes to outperform that. That's a tough ask for someone with one career start who is entering his age-23 season.

If we're judging Mahomes based on talent, all reports are that he has what it takes. Kansas City -- a team with the pieces to push deep into the playoffs -- isn't making this move if they don't think Mahomes can handle it. But to expect him to come out and perform as a top-10 passer from the jump is putting unfair expectations on him.

Take Deshaun Watson as an example. Watson was phenomenal before getting hurt in his rookie year. We'd all judge him as being a massive success.

He was still just 10th in Passing NEP per drop back, two spots behind Smith. It takes a whole heck of a lot to be on the same level as Smith was in 2017, and we shouldn't expect that Mahomes comes in and dominates right away.

Long-term, this is a different story. Kelce, Hill, and Hunt are all under contract through 2019, meaning they should get at least two years of Mahomes. Mahomes in his age-23 and age-24 seasons is likely going to be better than what they would have gotten out of Smith in his age-34 and age-35 seasons. Viewing it that way is fully logical and fair. But when you're comparing Mahomes to the 2017 version of Smith, expecting an even better performance is risky at best.

What About the Deep Balls?

The crux of the argument between Smith and Mahomes is each guy's skill and willingness to chuck it long. Smith has a reputation for being conservative while Mahomes had the best ball velocity at the 2017 combine. Deep balls should be his specialty. Given how often Kelce and Hill, specifically, get targets that far down the field, wouldn't Mahomes be an upgrade for them?

Again, it depends on how you're viewing the question. If you're asking whether Mahomes is a better deep-ball passer, the answer is likely yes. But if you're asking whether he'll be able to outperform the 2017 version of Smith, it's once again a difficult task.

We know Smith's reputation as a passer is of one who doesn't challenge defenses deep down the field. But 2017 was different. Not only did he press deep more often, but he did so effectively.

Below are Smith's numbers from 2017 on throws that traveled at least 16 yards beyond the line of scrimmage. His "Deep Rate" is simply the percentage of throws that traveled that far, and his Passing NEP per attempt is the total expected points added (again, deducting for negative outcomes, as well) divided by his total deep attempts. Success Rate is the percentage of attempts that increased the team's expected points for the drive, which is effectively his completion percentage on these throws.

In 2017 Deep Rate Passing NEP per Attempt Success Rate
Alex Smith 19.41% 1.01 47.96%
League Average 18.67% 0.42 39.58%

Not only was Smith above average in all three categories, but he was the league's third-best passer on deep balls (based on the Passing NEP per attempt of 30 quarterbacks with at least 50 such attempts). Even if you expect Mahomes to be a skilled passer, asking him to be better than what Smith did in 2017 is tough.

There is some room for upward mobility in the deep rate (Watson led the league in that category at 27.45%, and Smith was at 19.41%), and that could be the opening to boost thoughts on Kelce and Hill. But they already got plenty of volume down the field this year.

Excluding Week 17 (when both players sat), Kelce had 39.18% of the team's deep targets this year, and Hill was at 28.89%. Kelce was tied for the 11th-most deep targets in the league among all players, and he blew all other tight ends out of the water. How much more volume would you really expect to go their way with Mahomes at the helm? And if they do get that volume, will the throws be as effective as they were coming from Smith this year? That's a lot of assumptions to make if you think this will be an immediate upgrade for them in fantasy.


Based on what we have seen from Mahomes so far (and the faith the Chiefs have shown in him), it seems likely that he'll be a baller in the NFL. And he may wind up being an upgrade from Smith. That doesn't mean we should change the way we view this offense.

If you want to view Mahomes as an upgrade over Smith, that's fair, and it could absolutely be right. But when you're doing so, you have to make sure you're comparing Mahomes to what Smith would have done in 2018 as opposed to what Smith did in 2017. We have to account for some potential regression in the offense simply because it's hard to be as good as Smith was last year two times in a row.

In the long run, this is likely a win for the Chiefs, and it may help smooth out what would have been potentially harsh regression if Smith had remained the starter. But if we're using the transition to Mahomes as a justification for buying every member of the Chiefs' offense for fantasy football, we may need to check our expectations and make sure we're doing so for the right reasons.