Fantasy football: J.J. McCarthy’s injury hurts Justin Jefferson’s value

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Already, headed into Vikings training camp, the fantasy prospects for the NFL’s best receiver, Justin Jefferson, were aggravated by a hazy quarterback situation.

Now, there is some clarity. Rookie J.J. McCarthy has a meniscus tear in his right knee and will undergo surgery this week. That means we can expect QB Sam Darnold to begin the season as the starter.

There won’t be any firm timetable on McCarthy’s return at least until after the surgery. But best guesses range from missing the first few weeks in the best case, and the entire season in the worst.

Let’s just assume best-case scenario for a moment. That would mean McCarthy could return to action in about four weeks. That would mean missing the first two games before he starts practicing again.

Reminder: He is a rookie. So he is learning a new offense under new coaching with new teammates in a new league. It is not an easy thing to do, and missing a month of prime prep time impedes that transition. So let’s guess it takes at least two more weeks before he is game ready. That makes a reasonable, best case debut in Week 5. Not necessarily the most likely, but the most hopeful.

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That game happens to be against the Jets, in London, before a bye. It makes no sense to rush him back, so let’s say he sits that game, then has a bye week, which means his first real game action could come in Week 7 against the Lions.

Reminder: We’re painting this as the best case, by no means a guarantee. He could miss more time. It is safe to assume while he is out, Darnold will be under center.

Reminder: We mentioned clarity earlier. Imagine your windshield is covered in rain. You can’t see very well. You don’t have clarity. You turn on the wipers, now you can see. But that doesn’t mean the road ahead is going to be smooth just because you can see it. And we fear it could be a bumpy road ahead with Darnold.

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Those bumps could cause disruptions in Jefferson’s fantasy output. Now, we believe Jefferson is the most talented receiver in the game at his position. We think he is talented enough to overcome the hurdle that is Darnold and still post strong fantasy numbers. We’re not saying Jefferson is useless.

But we were already concerned about taking him with one of the top seven picks. And now, with the low-percentage probability of McCarthy having a great rookie season dipping even lower with the injury, that is a drag on Jefferson’s fantasy projection.

Reminder: Darnold has never delivered a blockbuster fantasy receiver season. He has four seasons in which he was the primary starting QB — three with the Jets, one with the Panthers. Here are his top fantasy receivers each season in PPR:

2018: Robbie Anderson (nee Chosen): WR39, 11.2 PPR per game.

2019: Jamison Crowder: WR26, 12.4.

2020: Crowder: WR39, 14.3

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2021: D.J. Moore: WR18, 14.0

For some quick and dirty math, let’s assume Moore is the only benchmark we want to use for Darnold pairing with a top receiver. And let’s assume Jefferson is 20 percent better than Moore.

Moore’s PPR output in 2021 was 237.5 in PPR. And 20 percent bump would put that number at 285, which would have been good for WR8 that season.

That’s not bad, right? The eighth-best wide receiver?

Reminder: This is using the best-case scenario for Darnold, without taking into account any other season or receiver in Darnold’s career history, just using the best season by his best receiver and building on that.

Nevertheless, let’s stick with a WR8 projection. That puts Jefferson more in line with second-round receivers this season — Puka Nacua, Davante Adams, Chris Olave, Michael Pittman Jr., Marvin Harrison Jr., Drake London, etc.

That’s not a bad group, but some of those guys have huge questions. And none of them are routinely picked in the top 5-7, where Jefferson often goes.

So the McCarthy injury has delivered some clarity. And what we see more clearly now is that Jefferson is even less likely to live up to his draft cost with Darnold as his QB.

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