49ers Roster, 90-in-90 breakdowns: Justin Smith

Here at Niners Nation, we're presenting a series called "90-in-90". We'll be looking at every player on the 49ers offseason roster, one player per post, from now until the start of training camp.

The 49ers locked up defensive end Cornellius Carradine to his rookie contract earlier this week, so it seemed as good a time as any to take a look at the guy who will serve as his mentor this year and potentially beyond.

The man they call Cowboy, Justin Smith, has been playing some out of his mind football with the 49ers. And yet even with what we've seen from him, particularly the last couple years, Smith remains both the most solid answer and one of the biggest questions on this team.

The 2012 season told us pretty much everything we needed to know about Justin Smith and his impact on the team. Smith was named second team All-Pro at both defensive end and defensive tackle. This was the second straight season he earned an All-Pro nod at two different positions. It was all the more impressive because he missed the final 2 1/2 games of the regular season.

Of course, that absence might have further proved just how great he is. The 49ers held on to beat the Patriots and split the final two games, but the defense struggled. The easy target of criticism was Aldon Smith, but a good chunk of the defense was feeling the burden of Justin Smith's absence. Smith did return for the playoffs, and the 49ers had a lot of success, but the defense was missing something in January and February.

Why he could improve in 2013

Just staying healthy would be a step in the right direction. This is where the addition of Tank Carradine and Glenn Dorsey could help. Justin Smith and Ray McDonald are workhorses, playing as many defensive snaps as anybody on the team. Carradine is rehabbing from an ACL injury suffered the day before Kyle Williams. He should be back for training camp. Dorsey is competing for the nose tackle role, but it is possible Williams wins that job and Dorsey ends up as a rotational player. They both could provide Vic Fangio with serious options to help keep Smith and McDonald fresh.

If Smith is healthy, he can handle the workload. Injuries are sometimes just freak accidents, and you can't completely plan for them. That being said, if Carradine and potentially Dorsey can be effective rotating on to the line, a fresher Justin Smith is a good thing for the 49ers defense.

Why he could regress in 2013

Justin Smith is not getting any younger. Even with full participation in 2013, that does not guarantee he does not take a step back. I do think he has another couple years at his current level of play, but there are no guarantees. That is one reason the 49ers drafted Tank Carradine. They signed Glenn Dorsey to help as well, but Carradine would seem like the logical candidate for defensive end of the future. Ideally the future is a year or two, or more, down the road. But we'll find out more as the season approaches.

Odds of making the roster

The real question is that rotation behind Smith along the defensive line. Smith and McDonald were among the league leaders in snaps the last two years prior to Smith's injury. Now we get to see whether the 49ers will adjust things even just a little bit. Fangio has given his starters serious playing time the last two years. I think we'll see some more rotation, but I honestly don't know how much. Part of this will depend on Carradine's ACL recovery. He should be back, but the 49ers are not going to rush him back. The beginning of training camp is going to tell us a lot.

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