Why Isaac Sopoaga's Tenure in the Bay Area Is Coming to a Close

It has been nine years since Isaac Sopoaga was drafted by the San Francisco 49ers in the fourth round of the 2004 NFL draft. That nine-year span has seen plenty of ups and downs as the 49ers struggled under the direction of Mike Nolan and Mike Singletary for years.

Things didn't come together for San Francisco until Jim Harbaugh took over in 2011, and seemingly that was the same time things started to click for Sopoaga. Before Harbaugh and defensive coordinator Vic Fangio arrived, the 330-pound nose tackle spent a majority of his career as an underachieving monster on the defensive line.

After recovering from a season-ending injury in 2004, Sopoaga finally made his NFL debut in 2005. Under Nolan he started his career at left defensive end in the 3-4 and continued on their until Singletary was fired at the end of the 2010 season.

During that six-year span, he registered 6.5 sacks and one forced fumble. Not to mention his play against the run was well below where it should have been amidst that same six-year time frame.

So, what did Harbaugh do when he took over?

He moved Sopoaga to nose tackle because he thought it was his most natural position. Most viewed San Francisco as nuts because they were letting Aubrayo Franklin walk after overachieving in back-to-back seasons in 2009 and 2010.

And by overachieving I'm not talking about quarterback sacks or quarterback hurries, I'm talking about his incredible play at the nose in the run game. In 2009 he accumulated 35 defensive stops, and in 2010 he upped that by recording 37 defensive stops.

Pro Football Focus had him graded out as the 17th-best nose tackle in '09 and the 13th-best nose tackle in the league in '10. It's hard not to be impressed by those numbers, yet Harbaugh knew something that the rest of us didn't because Sopoaga seemingly picked up right where Franklin left off.

Much like Franklin, Sopoaga excelled as an anchor by eating up blocks and keeping offensive linemen off of Patrick Willis and NaVorro Bowman. His solid play up front allowed him to swallow up 20 defensive stops and one tackle for loss in the run game.

After a season of such high quality, it was only fair to expect a similar season in 2012. However, a reduction in snaps due to opposing teams forcing the 49ers to deploy more nickel-and-dime packages doomed Sopoaga's consistency and worth.

Pro Football Focus had him down for a measly 31 percent of the team's defensive plays for the season. Which in turn means his bloated $3.8 million contract from 2012 could spell the end for Sopoaga as a member of the 49ers.

It's not out of the question to think the free agent could return at a reduced wage, considering his six quarterback pressures and 16 defensive stops in the run game aren't set to warrant him a fat payday anywhere else. Yet it's highly likely that San Francisco doesn't want him back for those same reasons.

He only started nine games and was often phased out of the defense game plan at times. Moreover, Sopoaga is on the wrong side of 30. By the time the 2013 season kicks off he will be 32 years old, and the 49ers could easily find a replacement who is 10 years younger for half the money.

The club also thinks very highly of Ricky Jean-Francois, who is a free agent as well. But the much younger, versatile nose tackle could easily be the starter if they found common ground in bringing him back. Jean-Francois will have suitors, but if he is smart he will stay in the Bay Area as he already knows what is expected of him at the nose.

For those who think Sopoaga would provide good depth—you may be onto something, except for the fact he still doesn't come on the cheap. As a nine-year pro his salary would be $825,000, and for the minimal snaps he would play, drafting his replacement is your best bet, backup or not.

Sopoaga has given his all to the organization, but at some point it's time for a change of scenery. And his time is now as the 49ers look to maximize cap space and potential—two things he currently has working against him as a player who is near the tail end of his career.

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