San Francisco 49ers Changing Linebackers: Aldon Smith In, Patrick Willis Out

One in, one out—that seems to be the motto for the San Francisco 49ers at linebacker this season.

In this week?  Aldon Smith, whose nine-game suspension is finally over.  It’s almost impossible to quantify just how great a player Smith is, but I’ll try—in the last three seasons, Pro Football Focus (subscription required) has ranked Smith as the second-, third- and fifth-best 3-4 outside linebacker in football. 

This isn’t just adding a starter back; this is adding a superstar to the defense.  This is adding one of the top 10 pass-rushing threats in football to a team that has been looking to sustain a pass rush all year long.

Billy Hurst/Associated Press

Out this week?  Patrick Willis, who is going on season-ending injured reserve with the toe injury he suffered back in Week 6.  He has apparently had a setback in his recovery and will in fact require surgery, according NFL Media Insider Ian Rapoport. 

Losing a future Hall of Famer and the heart of the center of the defense for the rest of the season is a crushing blow, especially coupled with the news that NaVorro Bowman is still suffering from a bit of knee pain, according to ESPN’s Ed Werder.

This means the 49ers' elite linebacking corps—a corps that not only normally ranks high on all the statistical charts but will count for four of the top five largest cap hits next season, according to Spotrac—will not play a single snap together this season.  That’s an incredible amount of talent and value that’s been left on the bench.

So, it’s a day for mixed emotions when it comes to the linebacking corps, for certain.  Replacing Willis with both Smith and Bowman is a net upgrade for the team, so it's still trending upward as the season goes along—but obviously, a team without Willis isn’t as good as a team with Willis.

The short-term result of all this will be a bit of a slow ramp-up.  Smith has been able to keep in shape during his nine-game suspension, but he hasn’t been able to practice with the team.  There might be some rust on him this week against the New York Giants, but a rusty Smith is still worth throwing out there.

Jack Dempsey/Associated Press

Perhaps the best comparison to Smith’s status is Von Miller, another uber-talented pass-rusher who came off a long suspension last year.  Miller was suspended for six games for attempting to cheat a drug test, and there were some worries that he’d come back to a slow start.

Not so, however.  In his first game back, against the Indianapolis Colts, Miller played 71 out of 75 snaps, according to Pro Football Focus (subscription required).  The well-rested Miller didn’t bring down Andrew Luck at all, but he was credited with two quarterback hits and six hurries.  He essentially picked up right where he had left off the season before.

It’s not like Smith is coming off an injury and will therefore be less able to move or something like that—Bowman’s the one the team will have to worry about there.  Smith should be in top physical form and ready to rock right out of the gates. 

If anything will be an issue, it would likely be his stamina—and rookie Aaron Lynch has been doing a great job filling in.  Perhaps, like last season, the 49ers will keep Smith out on about half the snaps on his first week back, letting Lynch fill in for the other half.  That’s still an improvement at pass rush.

I would actually like to see both Smith and Lynch on the field at the same time on pass-rushing downs. Lynch has been San Francisco’s most dynamic pass-rusher this season, whereas Ahmad Brooks has been comparatively quiet.  Letting Smith and Lynch attack opposite offensive tackles will overwhelm most opponents and could be a lethal one-two punch.

Ben Margot/Associated Press

Speaking of rookies, the 49ers might be cushioned somewhat from the loss of Willis by the increasingly great play of Chris Borland, the third-round pick out of Wisconsin.  Borland dropped some in the predraft process due to his non-prototypical size, but the man knows how to play football. 

Borland has 35 tackles in the last two games, which is absolutely insane.  He also recovered the fumble to set up the game-winning field goal in overtime against New Orleans.

Despite only having three starts, Borland is beginning to draw some attention for defensive rookie of the year honors.  Borland already has the fourth-highest grade among rookie defenders on PFF.

Player	Team	Position	Grade
Khalil Mack	Oakland	OLB	22.9
Aaron Donald	St. Louis	DT	20.5
C.J. Mosley	Buffalo	ILB	11.4
Chris Borland	San Francisco	ILB	10.4
Anthony Barr	Minnesota	OLB	10.2
Aaron Lynch	San Francisco	OLB	9.5
Jason Verrett	San Diego	CB	8.1
Preston Brown	Buffalo	OLB	7
E.J. Gaines	St. Louis	CB	6.6
Jonathan Newsome	Indianapolis	OLB	2.6

He might have a hard time actually winning the award, thanks to the fact that players such as Mack and Donald have been starting since Week 1, but Borland has been holding his own in the middle of the lineup.

No, he’s not Patrick Willis yet, and likely never will be—Willis is a future Hall of Famer, and that’s a lot to ask any player to live up to.  However, how many teams could take losing Willis and Bowman and have players such as Borland and Michael Wilhoite replacing them?  That’s a luxury.

Make no mistake; the loss of Willis hurts San Francisco’s chance of making the playoffs.  The 49ers still need to figure out a way to shut Marshawn Lynch down twice, for instance, and the team would feel more comfortable with Willis in the center of the defense than anyone else.  The presence of Borland is a silver lining, not a panacea.

This has been a very difficult season for San Francisco, suffering through injuries and off-field turmoil.  The team has been fortunate to avoid this for most of Jim Harbaugh’s tenure, and it’s coming back to strike the team with interest in 2014.

However, even with Willis’ injury, the 49ers are trending upward luck-wise.  It’s a sad fact that even with Willis’ injury, the 49ers will be healthier than they have been this season with the imminent return of Smith and Glenn Dorsey.  They’re still legitimately in the playoff race, albeit at the back of it, and might still make some noise this season.

It’s correct to be upset about Willis’ injury, but the return of Smith and the continued good play of Borland do help mitigate it.  This is a setback, but it's not a season-ending one for the team.

Bryan Knowles is a featured columnist for Bleacher Report, covering the San Francisco 49ers.  Follow him @BryKno on Twitter.