Looking at Pac-12 QB stats: Sean Mannion

The Pac-12 is loaded with talented quarterbacks this season, so this week we’re going to take a look at a few of the top returning signal-callers and what their statistics from past seasons show. We’ll start today with the player who broke the Pac-12’s passing record last season, Oregon State QB Sean Mannion.

Mannion hurt his left knee during the 2012 campaign (his redshirt sophomore season) and required arthroscopic surgery, causing him to miss two games -- BYU and Utah. In his first game returning to the field, Mannion threw four picks against Washington and was benched the following two games. Oregon State coach Mike Riley also gave the start to QB Cody Vaz in the Beavers' bowl game that season.

His statistics that year tell a lot about how much the injury affected him. (Note: These statistics exclude the 0-of-1 passing effort from Mannion against Stanford that season because to include one pass attempt in relief and count it as a full game's body of work would skew the averages.) His passing yardage per game game decreased from 339.5 yards per game before the injury to 272 per game after the injury. And though his completion percentage actually increased during that same time period (going from 63.3 percent in the first four games to 66.9 percent in his final four full appearances that season) his number of attempts per game dropped from 42.3 to 34.8. As a result, he averaged 26.8 completions per game before his injury and just 23.3 completions per game after the injury.

These post-injury stats are important to keep in mind when looking at Mannion's growth because that was his launch point for his junior season. His first four games as a sophomore were excellent, but the injury clearly affected him. So when he started building toward his stellar 2013 season, it's even more impressive when looking at the post-injury 2012 statistics rather than just all of his sophomore season statistics.

Mannion's touchdown-to-interception ratio is another great example of this. He ended the 2012 season with 15 touchdowns and 13 interceptions (1.2). But before the injury, that number was 1.8; after the injury it was 0.9. Again, that's where he was working from entering his junior season, but it was also the biggest area of improvement in Mannion's game between the 2012 and 2013 seasons.

In fact, of the top six quarterbacks in the Pac-12 who return in 2014, Mannion made the biggest improvement in his touchdown-to-interception ratio between the 2012 and 2013 seasons. Yes, Oregon’s Marcus Mariota had some crazy numbers there (7.8 touchdowns per every one interception in 2013, 5.3 in 2012). However, Mariota’s growth in that area was not as steep as Mannion's over the same time period (though, to be fair, if Mariota’s improvement had been the same as Mannion's, it would have meant throwing just two interceptions to his 31 touchdowns in 2013). But Mannion more than doubled his statistics there -- 2.5 touchdowns for every interception in 2013, 1.2 in 2012 (and almost tripled that stat if considering only the post-injury statistics).

Also, a major area of improvement over that same time period was in Mannion's third-down passing conversions. Between his post-injury sophomore season to his junior season, Mannion improved his third-down conversions by more than 5 percent (33.3 percent post injury in 2012 to 38.9 percent in 2013). That’s on par with the kind of improvements made over the same time period by UCLA’s Brett Hundley (36 percent in 2012 to 41.1 percent in 2013) and Washington State’s Connor Halliday (31.6 percent in 2012 to 36.7 percent in 2013).

Mannion’s statistics were relatively similar between his redshirt freshman and sophomore seasons. His steep improvement in his game happened before the 2013 season, which is also when Brandin Cooks emerged as a superstar, going from a 1,000-yard receiver to becoming the best receiver in the nation. Looking forward, it’ll be interesting to see how much of Mannion’s success was tied to Cooks or whether he can establish that kind of chemistry with another receiver or group of receivers.

With that background, let's take a look at Mannion's stats from the past three seasons:

Junior season (13 starts):

Passing yards per game: 358.6

Completion percentage: 66.3

Passing attempts per game: 46.4

Passing TDs: 37

Yards per completion: 11.7

TDs-to-INTs: 2.5

Third-down conversion percentage: 38.9

Sophomore season -- total (8 starts)*:

Passing yards per game: 305.8

Completion percentage: 64.9

Passing attempts per game: 38.5

Passing TDs: 15

Yards per completion: 12.2

TDs-to-INTs: 1.2

Third-down conversion percentage: 34.6

* excludes 0-for-1 relief performance against Stanford

Sophomore season -- pre-injury (Wisconsin through Washington State):

Passing yards per game: 339.5

Completion percentage: 63.3

Passing attempts per game: 42.3

Passing TDs: 7

Yards per completion: 12.7

TDs-to-INTs: 1.8

Third-down conversion percentage: 35.2

Sophomore season -- post-injury (Washington through Nicholls State, excluding Stanford):

Passing yards per game: 272

Completion percentage: 66.9

Passing attempts per game: 34.8

Passing TDs: 8

Yards per completion: 11.7

TDs-to-INTs: 0.9

Third-down conversion percentage: 33.3

Redshirt freshman season (10 starts):

Passing yards per game: 277.3

Completion percentage: 64.5

Passing attempts per game: 39.4

Passing TDs: 16

Yards per completion: 10.9

TDs-to-INTs: 0.9

Third-down conversion percentage: 38.2