Should the San Francisco 49ers Bench Colin Kaepernick for Blaine Gabbert?

San Francisco 49ers quarterback Colin Kaepernick has been brutal this season. There is no denying that fact.

Kaepernick has been held under 175 passing yards in three out of four games to start the season and has failed to record a passing touchdown in three of four games. Most of Kaepernick’s production this season came in garbage time against the Pittsburgh Steelers in a 43 to 18 schooling in Week 2.

Just two seasons ago, Kaepernick was considered the 49ers franchise quarterback and one of the league’s best young stars after taking over for the ultimate game manager, Alex Smith, and leading his team to a close Super Bowl loss in 2012

His play this season, however, has many wondering what backup quarterback Blaine Gabbert could do if given a shot at running the offense. Is it really that bad for San Francisco?

The Analtyics

While it sounds like a crazy idea to bench a player considered to be the franchise quarterback for a player considered to be a first round bust, is it the right call?

Delving into Kaepernick’s Passing Net Expected Points (NEP) per drop back, the results are as poor as expected. NEP is our signature metric here at numberFire. When a player contributes to the team's chances of scoring above expectation the player receives a positive NEP, and a negative score when the player does the opposite.

Kaepernick holds an extremely poor -0.09 Passing NEP per drop back through Week 4. Kaepernick’s Passing NEP per drop back has declined in each of the last three seasons: 0.17 in 2012, 0.14 in 2013, and 0.04 in 2014.

In Blaine Gabbert’s stint with the Jaguars, his Passing NEP per drop back was -0.19 in his rookie season of 2011 and -0.12 in 2012. On 858 career drop backs from 2011 through 2014, Gabbert has amassed a Passing NEP of -170.60 (-0.20 per drop back). 

In that same span, Kaepernick has dropped back 1,225 times and secured a Passing NEP of 128.13 (0.10 per drop back). That's basically 300 points of expected scoring between the two passers in a four-year span.

For comparison sake, the man Kaepernick replaced and current Kansas City Chiefs quarterback Alex Smith’s Passing NEP per drop back as a 49er was 0.04 in his final full season as a starter in 2011. Smith’s Passing NEP per drop back was 0.14 before being replaced by Kaepernick in 2012.

It’s debatable how much better Kaepernick has been since replacing Smith, but he's clearly been better than Gabbert.

On-Field Struggles

In back to back possessions to start the game in Week 3 against the aggressive Arizona Cardinals, Kaepernick threw two pick sixes. Kaepernick finished the game with four interceptions and only 67 passing yards. Week 4 was a only a slight improvement going 13 of 25 for 160 passing yards, zero touchdowns and 1 interception, leading the offense to just 3 points on the day.

Kaepernick has thrown a touchdown pass in just one game this session. Kaepernick has also struggled with turnovers and poor decision making. After throwing only 10 total interceptions all last year, Kaepernick has already thrown 5 interceptions through four games and taken 14 sacks, putting him on pace for 56 sacks on the year. He took a league high 52 sacks last season. He has also lost a fumble.

On the season the 49ers have been outscored 110 to 45, but all the offensive struggles can’t be placed solely on Kaepernick.

Wide receiver Torrey Smith was supposed to give Kaepernick the deep threat the 49ers have been lacking to play alongside ageless wide receiver Anquan Boldin and tight end Vernon Davis.

The departure of running back Frank Gore to the Indianapolis Colts in the offseason opened the door for running back Carlos Hyde to take over early down work with running back Reggie Bush playing passing downs. After exploding for 168 rushing yards and 2 touchdowns in a Week 1 win over the Minnesota Vikings, Hyde has been held in check. Hyde missed portions of Week 2 with injury, and game flow hindered Hyde’s production in Week 3.

Smith, Boldin, and Davis have made a few plays as pass catchers, but none have been the reliable producers Kaepernick needs. Davis left Week 3 with a knee injury and was inactive Week 4. Bush missed Weeks 2 and 3 with a calf injury. Kaepernick’s offensive weapons have yet to complete a full game without missing time.

Smith has just 17 targets on the year, but his Reception NEP per target (1.01) ranks fifth among 78 receivers with at least 15 targets on the year. He's been efficient when catching the ball, but his catch rate (52.94%, 59th in the group) continues to plague his ability to contribute consistently.

Boldin's Reception NEP per target (0.55) ranks 53rd among those receivers, and his catch rate (57.69%, 50th in the group) isn't much better than Smith's.

Davis has had a minor resurgence in terms of efficiency, as his Reception NEP per target (0.69) ranks ninth among 23 tight ends with at least 15 targets. Again, though, a poor catch rate (53.33%, 20th in the group) limits his impact.

As inconsistent as the offensive unit has been through four weeks, the 49ers defense, as expected, is no longer dominant. San Francisco’s defense currently ranks 26th in points per game allowed at 27.5 and 23rd in yards per game at allowed 377.2. They rank 28th in the league in Adjusted Defensive NEP per play.

Without a dominating defense to rely on, Kaepernick has been unable to find ways to outscore opponents. The defense was solid in Week 4, holding the Green Bay Packers to just 17 points and quarterback Aaron Rodgers to 224 passing yards and 1 touchdown.

Time for a Turnaround?

At 1-3 the 49ers aren’t officially done yet, but they down own a league-worst 1.1% chance to make the playoffs, according to our algorithms.

First year head coach Jim Tomsula has to find a way for his quarterback to regain some semblance to his form from two seasons ago.

The 49ers are on the road this week facing the New York Giants in a winnable Sunday Night Football matchup. At this point, the odds of Kaepernick turning around his disappointing start are greater than the chances of Gabbert resurrecting his career in San Francisco.

For now the 49ers have to stick with Kaepernick, but with another loss or two behind horrible quarterback play, they will have to turn the reigns over to Gabbert if only to see what he can do.