49ers Alex Smith Colin KaepernickAs promised, I’m revisiting the statistical comparison of Alex Smith and Colin Kaepernick I did nearly a month ago. In the previous, Kaepernick had just completed his fourth start, a game in which he and the 49ers dominated the Miami Dolphins, which was cause for me to conclude that Kaepernick and Smith were essentially the same quarterback and that neither was better than the other, nor worse for that matter.

As it turns out, this comparison will be more equitable than the previous, as both Smith and Kaepernick ended the season with 218 pass attempts. This means whatever conclusions drawn will likely be more representative of the truth. I didn’t alter Smith stats as a result of his short completion to Bruce Miller in Week 17. I didn’t see the point, to be honest. Really, that short completion and subsequent victory formation “runs” only injured Smith’s stats. So, what follows is Alex Smith’s stats from Week 1 through Week 13, and Colin Kaepernick’s from Week 11 through Week 17.

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Explanatory Note: Most of these stats are taken from TeamRankings.com. Others were calculated all by myself. Offensive penalties per game is not an official stat, so I couldn’t give you a ranking.

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Explanatory Note: These stats, unless noted otherwise, are provided by Pro Football Focus (PFF).  Also note that I’ve provided three different quarterback rating. The traditional NFL model, which most agree is flawed (Read about it HERE). ESPN’s rating, which ”is a statistical measure that incorporates the contexts and details of those throws and what they mean for wins,” (Read about it HERE). And PFF’s rating, which is takes the traditional NFL formula and changes the statistical inputs (Read about it HERE).

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Explanatory Note: Defense-adjusted Value Over Average (DVOA) is a stat developed by Football Outsiders (FO). According to FO, DVOA “takes every single play during the NFL season and compares each one to a league-average baseline based on situation,” and “it gives a more accurate picture of how much better (or worse) a team really is relative to the rest of the league.” To read DVOA, know that the lower the total score, the better the defense (Zero represents average). If a team’s DVOA is in the negative, that defense is good. If it’s in the positive, the defense is bad. Weighted DVOA is adjusted to give more weight to more recent games. That is, games earlier in the season do not affect a team’s DVOA as much as later games. Read more about DVOA HERE.

I’ve given you both. “Weighted Through Week Played” represents the opponent’s weighted DVOA during the week of the matchup. “Overall” is the team’s current, unweighted DVOA. I’ve also given you rank, which is a very easy means of determining the quality of an opponent both at the time of the match up and now.


I still believe that my original conclusion holds true: Kaepernick is no worse than Smith and Smith is no better than Kaepernick. They are, in essence, the exact same quarterback. That said, there are few stats I want to highlight.

The first of which is attempts of 20+ yards. Kaepernick has attempted nearly twice as many passes of 20+yards than Smith. Over the past four season, Smith threw such passes on just 9.67% of his total attempts. This isn’t necessarily an indictment of Smith’s ability, but it does reinforce the notion that Smith isn’t much of a risk taker. His unwillingness to take risks could hurt the team in two ways: defenses can focus on short and intermediate routes and it impedes the 49ers from putting up points quickly. It also makes it infinitely more difficult to stay awake while watching the team.

Despite being pressured more, Kaepernick takes fewer sacks. This could be related to Kaepernick’s athleticism, but Smith was pretty mobile himself. I think this difference is really the result of one of the biggest criticisms of Smith: How quickly he becomes uncomfortable in the pocket. Kaepernick seems willing to stay in the pocket to deliver the throw, where as Smith is more likely to take the sack.

The final stat I want to highlight is average yards per attempt (YPA). According to Kerry J. Byrne of Cold, Hard Football Facts, YPA is the single greatest indicator of success. Bryne found that:

  • Teams that win the passing YPA battle almost always win the game.
  • Teams that lose the passing YPA battle almost always lose the game.
  • The winningest teams in history are typically the teams with the best passing YPA average
  • The winningest quarterbacks in history are typically the quarterbacks with the best passing YPA average

For his career, Smith averages just 6.6 YPA. With Harbaugh, the number (7.5) is substantially better. Even still, Kaepernick’s trumps Smith and everyone else in the league.What’s even more impressive is that Kaepernick has gained nearly 62% of his yardage in the air. This currently ranks him fourth in the league. The three players above him in this ranking average 6.3, 7.3, and 7.9 YPA respectively. This suggests that Kaepernick is less dependent upon his wide receivers for yardage and more accurate on intermediate and deep route.

That said, while Kaepernick perhaps the better passer, the 49ers offense has declined. The team is averaging fewer first downs and a shorter average time of possession. The running game has stalled to some degree as well. Frank Gore hasn’t eclipsed 100 yards since Week 7 and the team yards per carry has shrunk more than 1.5 yards since Kaepernick took over as the starter. A number of factors could contribute to this decline, such as injury and opponent value, but one factor must be Kaepernick’s management of the run game and the team.

As some readers have pointed out, the most troubling aspect of starting Kaepernick is that we don’t know his floor. That is, we don’t know how bad he can be. But thus far, Kaepernick has acquitted himself well as the starter. He has obvious deficiencies, as any young quarterback does. Even with them, he hasn’t shown his floor is anything worse than untimely mistakes. In other words, he has yet to completely lose a game for the team. Even in the loss to St. Louis where his errors were converted to points by his opponent, Kaepernick still gave the team a chance to win.

And that speaks to the heart of the debate: Which quarterback gives the team a better chance at victory? The one who’s the better passer, or the one who’s the better game manager?