A couple of years ago, I asked how long it should have taken the Jaguars to move on from Blaine Gabbert. Today I want to revisit that general idea, but look at how long it takes the best quarterbacks to identify themselves as top-tier players. A couple of months ago, I looked at the greatest quarterbacks of all time. Using the top 75 quarterbacks from that list, I removed any player whose career began before the merger; that left me with 42 passers.

First, I looked at how each quarterback fared in relative Adjusted Net Yards per Attempt — i.e., ANY/A relative to league average — through their first 16 starts. Just over two-thirds of these passers were above average during their first 16 starts, with 1/3 of those quarterbacks being at least 1 ANY/A better than league average.  That group of fourteen quarterbacks — which Aaron Rodgers just falls shy of joining — can be categorized as above-average quarterbacks from the beginning. They are Kurt Warner, Dan Marino, Daunte Culpepper, Chad Pennington, Tony Romo, Mark Rypien, Jeff Garcia, Boomer Esiason, Ben Roethlisberger, Philip Rivers, Matt Ryan, Joe Montana, Steve McNair, and Ken Stabler. Obviously a number of those quarterbacks were not immediate starters in the NFL, but they did excel as soon as they became starters.

The graph below shows each of the 42 quarterbacks’ Relative ANY/A through their first 16 starts. The X-Axis represents the quarterback’s first year, and the Y-Axis shows their RANY/A value through 16 starts.

Now, let’s remove the 14 quarterbacks who had a RANY/A of at least +1.0 through their first sixteen starts. How did the other 28 quarterbacks fare in starts 17 through 32 in RANY/A? Eleven of them produced a RANY/A of at least +1.0 in their next sixteen starts: Bert Jones, Matt Schaub, Ken Anderson, Peyton Manning, Aaron Rodgers, Brad Johnson, Carson Palmer, Jim Everett, Steve Young, Dan Fouts, and Steve Grogan.

Just eight of these quarterbacks had below-average RANY/As in their second set of sixteen starts. Troy Aikman, Vinny Testaverde, and Terry Bradshaw were former number one overall picks who were drafted by very bad teams; they all started at least four games as rookies, and produced below-average numbers through both starts 1-16 and starts 17-32.   Michael Vick was a former number one overall pick who saw some immediate success — he had an above-average RANY/A through 16 starts (but was below +1.0 RANY/A), not to mention significant production with his legs — but he has had an up-and-down career. ^[1]To say the very least.

Warren Moon, Brett Favre, and Joe Theismann also produced slightly above RANY/A numbers through 16 starts, and then below average RANY/A averages in starts 17 through 32.  Other than Aikman/Testaverde/Bradshaw — and I think they deserve to be in their own group — that leaves just Drew Brees as the only quarterback in our sample to be below average through both his first and second set of sixteen starts.

If we eliminate the 11 quarterbacks who had RANY/A averages of at least +1.0 in starts 17 through 32, that leaves 17 quarterbacks who turned out to have very good careers but failed to be far above average through their first 32 starts. How did they fare in starts 33 through 48?

Here we see Drew Brees finally stand out from the pack. In addition, Mark Brunell, Trent Green, and Troy Aikman were at +1.0 RANY/A in starts 33 through 48.

That leaves thirteen quarterbacks who failed to be significantly above-average during any of their first three 16-game samples: Brett Favre, Tom Brady, Joe Theismann, Dave Krieg, Jim Kelly, John Elway, Donovan McNabb, Vinny Testaverde, Terry Bradshaw, Randall Cunningham, Warren Moon, Michael Vick, and Rich Gannon.

We’ve already discussed Bradshaw, Testaverde, and Vick: talent was never the issue with these quarterbacks, but a combination of factors prevented them from seeing immediate success. What about the other ten?

• Brady finished as slightly above-average in RANY/A in each of his first three seasons as a starter. He also picked up a pair of Super Bowl rings. This was back in the “Brady is a winner with mediocre stats” days. It’s safe to say he had “broken out” by most definitions of the term by the end of the 2003 season, but it wasn’t until 2004 that he had his first great statistical season, and it wasn’t until 2007 that he had his first Tom Brady(TM) level year.

• Favre was in a similar boat, minus the rings. He played well his first three years, but he wasn’t Brett Favre good. The Favre from ’92 to ’94 was a good but unspectacular quarterback, in a not too dissimilar manner to a Cam Newton or Andy Dalton (at least, statistically).

• Theismann was drafted in 1971, but went to the CFL for three seasons. He barely played with Washington in ’74 and ’75 (although he did return punts), and then started 5 games in ’76 and 6 in ’77, before becoming the full-time starter beginning in 1978. His 1979 season was very good — he ranked 8th in ANY/A — but the cutoffs chosen prevent him from standing out in this analysis. Theismann had only one truly great season of his career, which came in 1983, although he had other solid seasons in his career. He’s a unique character in that he didn’t make his first Pro Bowl until age 33, and then was out of the NFL at the age of 36 (no link required).

• Krieg, like Brady and Favre, was above-average (but below +1.0 RANY/A) in each of his first three sets of 16 games. After sitting as a rookie, Krieg started 45 games from 1981 to 1985, going 27-18 and posting strong (but not overwhelming) numbers. He was even better for the rest of the ’80s, and had a very good career, albeit one that puts him a few tiers below the Brady/Favre level. Could you see Dalton turning into this generation’s Krieg?

• Kelly’s numbers hovered just north of league average during his first three years, but frankly, his career statistics are not commensurate with his reputation (albeit without adjusting for the fact that he played half of his games in Buffalo). His 4th and 7th years were very good, and his 5th and 6th years were great, but that was about it; of course, Kelly also lost three years to the USFL. He was a good-to-great quarterback almost immediately, though, so you wouldn’t cite Kelly as an example of how some quarterbacks take time to develop.

• I’ve already written at length about Elway’s numbers.

• McNabb’s numbers show a quarterback who steadily improved, but was still roughly league-average through his first five seasons. That’s a bit misleading, in my view, as the Eagles fielded some of the worst receivers in the league during that time, and McNabb added significant value with his legs. During his first 48 starts, the Eagles went 31-17; that lofty record was certainly a function of the team’s defense, but McNabb made three Pro Bowls during that stretch, too. Like Elway, I’d say early-career McNabb was better than his numbers.

• Cunningham was another Eagles quarterback who was a bit undervalued by looking at just his passing stats. Cunningham was an even bigger threat on the ground than McNabb, and was stuck playing in Buddy Ryan’s offense. Cunningham finally produced strong passing seasons in 1990 and 1993 before his scorched-earth run off the bench with Minnesota in 1998. Cunningham was bad — really bad — during his first two years, but he quickly settled down into at least a decent passer and a dynamite runner by the time he was 24 years old.

• Moon is in some ways a de facto number one pick, by virtue of landing with an absolutely horrible Oilers team. His numbers were not impressive during his first three years, but beginning in year four, he began building the groundwork for his Hall of Fame career. Moon’s career is unique, of course, but he does seem to have a bit in common with the Testaverdes, Youngs, Aikmans, and Bradshaws of the world when it comes to being brought in as a franchise savior for a bad team and struggling with such a Herculean task. P.S. Andrew Luck is pretty freakin’ good, isn’t he?

• The last quarterback on the list is another unique player. Gannon sat his first three years, and then generally performed as a below-average quarterback during his next three seasons as the Viking starter. He then went to Washington and struggled in 1993, and missed the 1994 season with a shoulder injury. He sat on the bench in Kansas City in ’95 and ’96, but played well in five starts in 1997. He kept up his solid play in ’98 over ten starts, before going to Oakland and making the first of four straight Pro Bowls at the age of 34 in 1999. I’m not sure if we’ll ever see another career quite like that one.

Conclusion

I looked at the best 42 quarterbacks to enter the league since 1970. Then I divided each quarterback’s career into sets of 16 starts. Just four of those quarterbacks produced below-average passing numbers in each of their first two sets of 16 starts: three former first overall picks (Bradshaw, Aikman, Testaverde), and Brees. If a quarterback is below-average through two years worth of starts — say, Ryan Tannehill — then it seems highly unlikely that such a player will turn into a franchise quarterback absent extenuating circumstances. In the case of Bradshaw/Aikman/Testaverde, the extenuating circumstances were landing with terrible teams; for Brees, well, he also landed with the worst team in the league: the Chargers went 1-15 the year before he arrived, and Brees was the first pick in the second round.

For Tannehill, the extenuating circumstances could be an offensive line that blocked and acted like high school girls. There are other “excuses” one could make for him, but in general, I don’t think his situation was analogous to what some of those other quarterbacks inherited. If Tannehill turns into a star quarterback, he’ll be a very unique case.

On the other hand, if we set our baseline north of league average, a number of star quarterbacks failed to average at least +1.0 RANY/A through two years worth of starts. Some of those quarterbacks were solid but not spectacular (Brady, Favre, Krieg, Kelly), others had unexpected bursts of late career success (Theismann, Gannon), while some were stuck in rough situations (McNabb, Cunningham, Elway, Moon). If a quarterback has been mediocre after two years worth of starts, the quarterbacks you want to point to are Aikman/Testaverde/Bradshaw/Brees/McNabb/Cunningham/Elway/Moon. ^[2]Expecting anyone to be the next Theismann or Gannon is to expect the improbable. But the odds are much more likely, I suspect, that they just turn into the next Mark Sanchez.