NFL player prop of the day: Expectations for Dak Prescott have grown

The easiest prop bet last season was punching the over on Dak Prescott's passing yards.

The total for the Dallas Cowboys quarterback was a smidge over 4,100 and that was way off. Dallas had a trio of fantastic receivers and Prescott never had a problem putting up good numbers.

Sure enough, Prescott was on pace for about 6,000 yards through four games. He wasn't going to keep up that pace but just needed to be somewhat decent the rest of the way to cash over 4,100 yards.

Remember, there's no such thing as a lock. Even when you're well on your way to cashing the ticket.

The rub about season-long props

As we know, Prescott didn't get to 4,100 yards. He broke his leg on a tackle and missed the rest of the season, stuck on 1,856 passing yards. If you had a ticket on Prescott under yards, you can't complain about bad luck for a while.

BetMGM has released player props for the 2021 NFL season and we'll break many of them down before the season starts (it's not bad prep for your fantasy drafts either). And the Prescott bad beat is a reminder: More can go wrong with season-long props than can go right.

Prescott's passing yardage total for this season is 4,775.5 at BetMGM, a big jump from 2020. Part of that is the addition of the 17th game (it'll take a while to get used to the new math, just multiply by 0.941 to convert it to a 16-game total you might be more comfortable until we're used to 17-game benchmarks). But mostly the books know they were way off on Prescott last season and aren't giving that one away again.

The trap with many player props is we lean toward optimism. It's easy for us to project the best possible outcome. Prescott has those three great receivers back and the defense is still not great. He'll be throwing plenty.

Yet, the under seems like the right play. That's a lot of yards and we don't know how healthy Prescott is. If he misses any games, the over will be even harder to reach. If the defense has improved and Ezekiel Elliott rebounds, Prescott won't be throwing as much as the first month of last season. There's also a chance Prescott sits in Week 18 with playoff seeding clinched.

More can go wrong with a player prop than can go right. It wouldn't be a total shock if Prescott had a 5,000-yard season. But there are questions, and that 4,775 mark won't be easy to reach.

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