Four seasons ago, Blake Bortles broke fantasy football.

It can be argued that Bortles also broke the Jacksonville Jaguars, at least partially, but he definitely broke fantasy football. He managed to finish fourth among all quarterbacks in fantasy scoring in 2015 despite leading the NFL in interceptions (18), fumbles (14) and sacks (51). Bortles completed only 58.6 percent of his throws, ranked No. 23 in the league in passer-rating (88.2) and his team went 5-11. He was verifiably not good.

And yet there he was at the end of the season, fourth at his position, ahead of Drew Brees and Aaron Rodgers.

Of course Bortles wasn't the first sketchy quarterback to elevate himself to fantasy stardom as a result of high-volume chucking (606 attempts) and sneaky-good rushing numbers (310 yards). He was, however, the most glaring example of the disconnect that exists between fantasy and on-field value. We should do better. To some extent, fantasy football now informs public perception of the relative talent of hundreds of players, so let's make an effort to fix our most obvious problems.

Before we dive into an overview of the quarterback position for 2019, please indulge a quick series of scoring and format recommendations for league commissioners. Let's begin with a quick fix to our biggest QB issue:

Switch to Superflex

That is, add a flex position to your league that can be filled by a QB. When you double the number of quarterbacks who need to be rostered in your league, you enhance the value of the elite players. As it should be. It's insane that typical fantasy settings exaggerate the importance of a role the NFL itself views as fungible (RB) while devaluing the game's most important position (QB).

Punish giveaways

In reality, a turnover is often a catastrophic, field-flipping event. In fantasy, turnovers are a minor inconvenience -- never more than a two-point penalty. My suggestion is this: Whatever point value your league assigns to passing touchdowns (usually four), deduct the same for INTs. When Bortles tosses 18 picks in a season, we need to fully account for his game-killing recklessness.

Let's reward accuracy

Or at least let's try. It's always felt wrong that fantasy leagues don't acknowledge the most valuable trait of the NFL's most valuable players. An easy (if somewhat sloppy) way to do this is to award small bonuses for completions -- let's say 0.25 points -- with a corresponding deduction for incompletions. So if your quarterback goes 20-for-30, he earns 2.5 points. If he goes 15-for-30, he gets nothin'. If he's 10-for-30, he loses 2.5 points (and John Elway immediately signs him).

I'm also an advocate for greater passing yardage bonuses, first-down scoring and any number of additional tweaks that enhance the impact of quarterbacks in our fantasy lives. We need the position to matter in our game, and not simply in the rare seasons in which some player goes supernova, Mahomes-style.

However, our purpose here today is to prepare you to draft the position as it presently functions in fantasy, not as it should. So let's dive into the 2019 QB pool.

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Current Quarterback Landscape

For fantasy purposes, this spot has never been as rich with high-scoring talent as it is right at this moment. Twelve current NFL starting quarterbacks have produced top-five positional finishes in fantasy over the past three years. Six different active starters have led the position in fantasy scoring at some point in their careers: Mahomes, Wilson, Newton, Brady, Brees, Rodgers. Of the seven players in history who've produced 5,000-yard passing seasons, five are current starters: Mahomes, Brees, Brady, Roethlisberger, Stafford.

Basically, you cannot screw up at quarterback in a fantasy league with a standard configuration. Replacement value at the position is ludicrously high. There is generally no penalty to be paid for drafting a bust at QB, because you'll have little trouble finding a 4,000-yard passer (or better) on the waiver wire in a 10 or 12-team league.

Tom Brady, the name that begins any greatest-of-all-time conversation, is currently sitting at No. 21 in the Yahoo composite QB ranks for 2019. That is how deep this position has become. It's silly. This is why so many of us argue for superflex formats, which require you to consider the position near the top of your draft. Otherwise, well...

Quarterback Draft Strategy

As ever, the best way to approach quarterback in a typical league is to forget the position even exists for the first 8-10 rounds. Don't allow yourself to consider it. Again, the depth at this spot in a 10 or 12-team league is just stupid.

Matt Ryan, last year's No. 2 overall fantasy scorer, is the eighth QB off the board in an average Yahoo draft. Ben Roethlisberger, coming off a 5,129-yard, 34-touchdown season, is QB14 in ADP. Dak Prescott, who has never ranked lower than 12th at his position in any season, is QB18.

So yeah, you can wait. And when you think it might be time to draft a QB, you should probably wait another round. It's just a crazy-deep position in non-superflex. We can guarantee that your league will not successfully draft every QB who eventually produces top-12 fantasy value. Also, because quarterback fantasy scoring is terrible, there's going to be only modest separation between QB3 and QB12 in year-end fantasy points. Individual matchups can be exploited throughout the season, too. Wait. WAIT.

Seriously, for the love of Jeff George, wait.

But what about Mahomes?

Clearly if we could guarantee another 5,000-plus passing yards and 50 touchdowns for Mahomes, he would be an exception to the wait-for-your-fantasy-quarterback rule. He and Peyton Manning are the only QBs in league history to reach those plateaus in the same season. (Mahomes, Manning and Brady are the only passers to reach both of those marks in any season.) But we can't establish 5,000-50 as some sort of baseline expectation for any player, at any talent level.

Even if you believe Mahomes is a one-man revolution at his position, directing the greatest offensive machine the NFL has yet seen, you still shouldn't forecast anything close to 50 touchdowns. There's no precedent for any quarterback maintaining, over several seasons, the sort of TD percentage (8.6) or yards per attempt rate (8.8) that Mahomes produced last year. It's not a reasonable expectation.

The good news is that Mahomes can encounter significant statistical regression yet comfortably finish first at his position in fantasy scoring. Remember, no other quarterback reached 40 touchdown passes last season; Ryan and Roethlisberger were the only other players who topped 4,700 passing yards. If Mahomes delivers, say, 4,800 yards and 38 TD passes in 2019, he's very likely to again rank first at his position. But those numbers wouldn't justify an early fantasy selection.

Additionally, we should point out that the history of top-of-draft fantasy quarterbacks is horrid. It was a bad idea to spend a first on Kordell Stewart in '98, Daunte Culpepper in '05, Manning in '05 and '14, Brady in '08 and Michael Vick in '11. Don't do it, people.

Key Stat Used to Evaluate QBs

Wouldn't it be nice if a single stat had the sort of predictive power necessary to sort the entire QB pool for fantasy managers? Well, no such luck. Sorry.

Quarterbacks have multiple paths to achieving fantasy value, making this a fascinating and complicated position to sort. Josh Allen, for example, was a mostly atrocious passer last season (6.5 Y/A, 52.8 comp%) who nevertheless carried fantasy owners late in the year, thanks to a series of heroic rushing performances. Philip Rivers, on the other hand, is an absolute statue of a human who rushed for only seven total yards in 2018, yet finished as a top-12 fantasy QB because he remains a surgical passer.

If you're looking for a single stat that tells us a lot about a quarterback's passing profile -- accounting for accuracy, decision-making, efficiency and team context -- then yards per attempt (Y/A) is useful. It's hardly the answer key, but it's a nice shorthand way to examine passers for fantasy purposes. Passer-rating is also fine, if flawed.

Top-12 Fantasy QBs

Per the Yahoo composite expert ranks: 1) Patrick Mahomes, 2) Deshaun Watson, 3) Andrew Luck, 4) Aaron Rodgers, 5) Matt Ryan, 6) Baker Mayfield, 7) Russell Wilson, 8) Cam Newton, 9) Drew Brees, 10) Carson Wentz, 11) Kyler Murray, 12) Jared Goff.

Andy’s ranks, freshly baked:

Draft-day Steal

If I have to name only one, it's hard to ignore Dak Prescott. Again, he's finished each of his three pro seasons as a top-12 fantasy quarterback, thanks in part to his reliable rushing contributions (18 career rush TDs). But for reasons unknown, Dak is the No. 18 QB off the board in ADP and No. 14 in the expert composite ranks (which is not my fault). He's a near-lock to finish as a starting-quality fantasy QB. He'll have a full season with Amari Cooper, which certainly helps.

It feels wrong to profile the QB position without touting dual-threat rookie Kyler Murray, so let's give him an honorable mention in the draft steal discussion. He's a brilliant runner with a terrific arm and plenty of weapons, at the controls of a potentially explosive offense. We've already hyped him several times throughout the offseason, so it's not as if he's flying under the radar.

Remember, quarterback is a spot at which you can draft exclusively for upside in standard formats, because so much talent goes undrafted. If Murray's play doesn't match the hype, you can move on without penalty.

Follow Andy: @AndyBehrens

More Positional Previews: Running Back | Wide Receiver

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