Given the success of guys like Matthew Stafford, Kirk Cousins, and Sam Darnold under his watch, Minnesota Vikings head coach Kevin O'Connell has built the reputation of being a quarterback whisperer during his last handful of years on the sidelines.
O'Connell's recent achievements with these veteran signal-callers are why few were skeptical of the Vikings' decision to select former Michigan quarterback J.J. McCarthy in the first round of the 2024 NFL Draft almost two years ago.
Due to multiple injuries, however, McCarthy has only appeared in a total of two games during his short tenure with Minnesota. He's unfortunately earned an injury-prone label already, and even during his two games on the field this season, his performance left plenty to be desired.
Is J.J. McCarthy the right QB for Minnesota Vikings head coach Kevin O'Connell?
Yes, O'Connell has had a bunch of success with quarterbacks during the last few years. But the majority of the guys that he helped steer in the right direction entered their relationship with the head coach with several years of starting experience at the NFL level.
Stafford had already started 165 games in his pro career before working with O'Connell when the current Vikings head coach was the Los Angeles Rams offensive coordinator in 2021.
In 2022, Cousins had 145 starts under his belt before O'Connell became his new head coach in Minnesota, and in 2024, Darnold joined the Vikings with 56 starts in his NFL career.
Before working with the Minnesota head coach, all three of these quarterbacks knew what was necessary to remain in the starting lineup at the pro level. What O'Connell did was help these passers reach their ceilings and get the absolute most out of their skill-sets.
While Minnesota's head coach was able to help this trio of veteran quarterbacks reach their goals, his track record with young signal-callers isn't often discussed. But when it comes to McCarthy's future, this element of O'Connell's past needs to be factored in.
During his career in the NFL on the sidelines as a quarterbacks coach, offensive coordinator, or head coach, O'Connell has struggled to help signal-callers aged 25-years-old or younger reach their full potential.
When looking at the quarterbacks aged 26 or older who have worked with O'Connell, the success rate has been much, much higher.
Now, for context, since some who are reading this are possibly ripping their hair out at the notion that O'Connell hasn't been successful with every quarterback that he's ever worked with in his NFL coaching career.
When it comes to Johnny Manziel and Dwayne Haskins, O'Connell was not a head coach when working with both of these players, so it's possible that he didn't get the final say when it came to deciding when either of them should start playing.
However, both Manziel and Haskins entered the NFL as first-round picks, and even with O'Connell's help, neither of them were able to reach their full potential when working with the Vikings' head coach.
For Manziel, it's okay to give O'Connell a pass for not getting the most out of him when they were both members of the Cleveland Browns in 2015. The former Browns quarterback had a number of off-the-field issues that he was dealing with in his pro career, and it ultimately led to a very early NFL exit in 2016.
If anyone was going to help Manziel succeed in the league, O'Connell probably had the best shot since he was actually the ex-Cleveland signal-caller's private quarterbacks coach leading up to the 2014 NFL Draft. But not even O'Connell could prevent Manziel from getting in his own way.
The sample size for the quarterbacks who are 25 or younger is also much smaller than the one for the passers who are 26 and older. But even the small sample size paints a clear enough picture.
Based on the data alone, O'Connell has not yet proven in his NFL coaching career that he can properly mold and develop a young quarterback.
Could this change with McCarthy? Absolutely, and McCarthy's ceiling is easily higher than any of the young quarterbacks that O'Connell has worked with in the past.
However, it's possible that O'Connell's magic might only work on signal-callers who have been in the league for at least a handful of seasons already.
He still has plenty of time to prove this theory to be wrong if he can get McCarthy down the right path, but based on the data, that's very far from a guarantee.