Jameis Winston vs. Marcus Mariota: Here's why one is closer to being next great QB

Writer's note: This story was filed before the Buccaneers' Thursday night game against the Falcons. All statistics are accurate as of the morning of Nov. 3.

Peyton Manning retired after throwing wobblers all the way to the Super Bowl. Aaron Rodgers is no longer the fire-breathing dragon version of Aaron Rodgers. Carson Palmer's peak appears to be over. Ben Roethlisberger is 34 and can't stay healthy. Drew Brees is 37 and stuck on the middling Saints. And at some point in the future, Tom Brady will decline -- sure, at that point, the NFL will be officiated by robots and Brady will be fully outfitted with Darth Vader's suit, but that day will eventually come, probably.

The point is, the NFL is in need of some new great quarterbacks. It's not that poor quarterback play is the reason why the quality of the NFL has dipped; that might be a myth. It's not that good, young quarterbacks don't already exist; Derek Carr is tearing it up, Dak Prescott might be good enough to steal away Tony Romo's job, and Carson Wentz has flashed potential.

It's just that we're nearing a time when the greats we've come so accustomed to watching every Sunday won't be there for us anymore. We're nearing the next generation of quarterbacks. And regardless of how you view them -- for every Carr and Prescott there's an Osweiler and Bortles -- there's no doubt you'll miss Brady and Brees when they're gone, because there's no one else at that level yet.

And that's why Jameis Winston and Marcus Mariota are so important. They both have a chance to help ease the transition. Taken first and second overall in the 2015 NFL Draft, Winston and Mariota have now been in the NFL for a season and a half. In the lead up to that draft, there was a serious debate over which quarterback the Buccaneers should draft with the first pick. It ended up being Winston, but that doesn't mean the debate has to end.

Given we're at a natural evaluation point, let's do exactly that. It's Winston vs. Mariota at the halfway mark of their second season. Both look like solid quarterbacks who have the potential to turn into great quarterbacks, but who's ahead in that race so far?

Overview

Here's what the passing statistics say from their careers so far:

So, using a pretty basic level of analysis, it's Mariota who looks like the better quarterback. And that's without even throwing in the fact that Mariota has out-rushed Winston by 195 yards despite the fact he's played in three fewer games (23 to 20).

But PFF graded Winston as the 13th best quarterback and Mariota as the 21st a year ago. Entering Week 9, PFF had Winston at 19th and Mariota at 30th. By PFF's standards, Winston is the better quarterback.

So, let's dig a little deeper.

The home-run ball

In his rookie season, Winston impressed with his deep ball. Per PFF, on 64 attempts that were thrown at least 20 yards downfield, Winston completed 23 for 730 yards, five touchdowns, and just one interception. He posted a 99.1 passer rating, which was the ninth-highest passer rating among all NFL quarterbacks -- just one spot behind Aaron Rodgers -- according to PFF.

Yet Winston's deep ball has regressed substantially through his first seven games of the 2016 season. He ranks 21st in passer rating (75.8) on those same passes -- funnily enough, he's positioned one spot ahead of Rodgers. In all, he's gone 10 of 36 for 279 yards, six touchdowns, and two picks. So, his yards per attempt went down from 11.41 to 7.75.

Why his decline on the deep ball happened is a bit more complicated. I'd argue it has to do with Winston's accuracy and ball placement, which is erratic. A year ago, Winston's accuracy percentage (which measures a quarterback's accuracy by giving him credit for dropped passes and discounting throwaways, spikes, batted balls, and fluttered passes that were thrown as he was hit) on deep passes was 42.2 percent, which slotted in as the 11th best percentage.

This year, it's 33.3 percent, which is tied for 17th. His percentage is the exact same as Brian Hoyer's, who happens to be allergic to big plays.

Mariota, on the other hand, was not a good deep passer when he entered the league. In 2015, he ranked 22nd (out of 22 qualified passers) for the lowest passer rating (32.8) on passes thrown 20-plus yards downfield. He went 9 of 49 for 293 yards, three touchdowns, and five interceptions. So no, he wasn't good.

This year, though, he ranks eighth in passer rating (114.6) -- though it's worth noting the sample size is small. He's thrown 24 deep passes (tied for 20th) and just 9.7 percent of his overall pass attempts qualify as deep passes (tied for 21st). So, the Titans and Mariota have been selective when asking him to go deep, but it's working when he does uncork them.

He appears to be improving -- at least slightly -- with his ball placement on the home-run ball. Take this perfectly lofted pass against the Jaguars a week ago.

Still, we'll give the edge to Winston because he's been better for a longer period of time. It's clear, though: Both are inconsistent.

And it's certainly worth noting that Mariota averages more yards per attempt than Winston. But in terms of just deep passes, Winston holds the advantage, which isn't necessarily surprising given he's had the luxury of tossing up jump balls to Mike Evans, who is beyond capable of rescuing errant passes.

Mariota hasn't had that luxury.

Accuracy

It's Mariota who wins out in accuracy. He wins easily in completion percentage and in more advanced metrics. Using PFF's adjusted completion percentage statistic, which "accounts for dropped passes, throwaways, spiked balls, batted passes, and passes where the quarterback was hit while they threw the ball," Mariota comes out above Winston.

In 2015, Mariota's percentage sat at 71.4. Winston's sat at 69.1. Both, however, were near or at the bottom of the table. Mariota ranked 21st and Winston ranked 27th out of 27 qualified passers.

This year, Mariota's percentage rests at 70.6. Winston's rests at 66.8. Mariota ranks 24th -- again, not good. Winston ranks 29th -- again, last. Even when he completes passes, Winston often makes life difficult for his playmakers with poor ball placement. Mariota also struggles with consistency, but more so on passes deep down the field.

On short to immediate passes, Mariota is more dependable.

Winston struggles with his accuracy on shorter passes. He is the quarterback who will loft in an absolute dime for a touchdown ...

... just a few plays after missing an open slant route.

He's alarmingly inconsistent with ball placement.

Under pressure

One of the hallmarks of a great quarterback is his ability to deal with pressure -- not necessarily the pressure of a big moment, but the pressure of a 300-pound lineman sprinting toward him at full speed. Thankfully, PFF tracks that kind of data.

In 2015, Mariota's 82.8 passer rating under pressure placed seventh in the NFL. Winston's 63.3 passer rating ranked 22nd out of 27 qualified passers. In 2016, Mariota ranks 13th with a 66.5 passer rating under pressure and Winston ranks 10th with a 73.2 passer rating.

Here's what their career numbers look like when they've been under duress:

In fairness to Winston, he's been under pressure on a far higher percentage of his dropbacks -- 37.8 percent last year and 38.9 percent this year. Mariota's pressure rates? 35.0 percent last year and 27.9 percent this year.

Which brings us too ...

Supporting casts

If you'd asked me a year ago, I'd say it was Winston who had the better supporting cast with Doug Martin, Mike Evans, Vincent Jackson, and Austin Seferian-Jenkins (at one point we all thought he was a decent to good tight end prospect). Winston also wasn't forced to deal with adjusting to pro style system given he played college ball at Florida State.

Mariota, on the other hand, came from Oregon's spread offense system. He didn't have a running back or a legit No. 1 receiver. He did, at least, have Delanie Walker -- one of the most under-appreciated tight ends in the game. Still, it was Winston who had the best shot of coming out of the gate firing.

But Mariota outplayed Winston with a worse supporting cast. He completed a higher percentage of his passes, averaged the same yards per attempt, posted a higher touchdown rate and a slightly lower interception rate. Mariota was the better quarterback, even though Winston seemed to get more attention.

This year, I'd give the supporting cast edge to Mariota. Though he's saddled with Mike Mularkey and his dumb offensive system -- for more on that, read Cian Fahey's excellent piece -- you can't deny that the exotic smashmouth is getting results on the ground. DeMarco Murray is second in the league in rushing yards (756) and he's averaging 4.7 yards per pop while rookie Derrick Henry has added 221 yards in a secondary role. As a team, the Titans rank third with 152.3 rushing yards per game.

That's about it, though. He still doesn't have a clear legit WR1 -- no Tajae Sharpe did not turn into the sleeper of the year despite our best wishes. Walker, a tight end, leads the team in receptions.

And Winston still has Evans, who trumps Mariota's entire receiving corps. Evans has caught 118 passes since Winston entered the league in 2015. In that span, the Titans' leading wide receiver is Kendall Wright. He's caught 53 passes since the beginning of the 2015 season.

But Winston's running game has taken a hit due to injuries (Martin's played in two games this year) and his offensive line doesn't come close to comparing to Mariota's. As previously mentioned, Winston's been pressured on 38.9 percent of his dropbacks this season, which is pretty much the exact same percentage as Sam Bradford, who we've basically declared dead already.

Who's better?

Marcus Mariota is a better quarterback than Jameis Winston. He doesn't feature a better deep ball than Winston, he doesn't boast a better arm, and he doesn't look like a prototypical quarterback in the way that Winston does, but he's better -- at least at this point.

His game, which is built around accurate short to intermediate passes, is more consistent. He's also improving in the areas in which he struggled a year ago -- the deep ball, though it's not clear just how much he's improved because the sample size is still too small. I'd take him in an instant over Winston, who has remained just as inconsistent as he was in his rookie season.

In six career games, Winston's posted a passer rating above 100. In nine career games, he's posted a passer rating below 80. He's hit or miss in so many ways.

Winston supporters will undoubtedly point to his upside -- look at that arm -- but at some point Winston will need to demonstrate he can be accurate with that arm. His accuracy will have to improve if he's to develop into a top-level passer. Until he does that, he'll remain a middling, inconsistent quarterback who goes through extreme peaks and valleys.

Like Winston, Mariota is also prone to peaks and valleys. He's also inconsistent. But Mariota has also pieced together more 100-plus passer rating games (7).

He's also trending upwards compared to Winston, who has stagnated. Mariota has improved this year in completion percentage, touchdown rate, interception rate, and passer rating. Winston has improved his touchdown rate, but has worsened in yards per attempt, interception rate, and passer rating.

At this point in their careers, Mariota has been the better statistical quarterback. And he looks like the better bet to develop into the next great NFL quarterback, though both have a long ways to go to reach that status.

Wink of the CBS eye to Pro Football Focus