Each year, we like to run a series of posts called "90-in-90." The idea is that we'll take a look at every player on the roster, from the very bottom to the top and break them down a few ways. This roster will certainly change, and some days we'll have more than one so it's not exactly 90 players in 90 days. At this point, it's a name we're keeping around for street cred.

Is there anybody on the 49ers defense that flies under the radar quite like defensive tackle Ray McDonald? It is probably fitting then that he plays on the same side of the field as Ahmad Brooks, given how underrated he sometimes can be.

McDonald is coming off his third season as a starter, which followed four seasons as a defensive reserve. His 2013 season was nothing spectacular, but it was perfectly solid. If you're a fan of Pro Football Focus grading, he had some highs and lows, but he never peaked too high or shot down too low. It is worth noting this all came amidst a season in which McDonald was slowed by a couple injuries.

In Week 5, he suffered a partially torn biceps muscle. He played through the injury the remainder of the year, getting it surgically repaired after the playoffs. In Week 10 against the Carolina Panthers, McDonald suffered a high ankle sprain. He sat out the next two weeks against the New Orleans Saints and Washington, with Tony Jerod-Eddie starting in his place.

We can all complain about the call against Ahmad Brooks, but you have to wonder if a healthy McDonald might have been a difference-maker in such a close game. Tony Jerod-Eddie is a solid reserve, but McDonald has proven to be a very solid starter. McDonald came into the league as a guy who was quick off the end, and a potential pass rush threat. He showed the pass rush skills fairly well in 2011, but for the most part it's been about strength and brute force. I won't say he's a "poor man's Justin Smith", but he is a productive defensive tackle without putting up huge numbers. I don't know if that's the best way to compare it, but that's sort of what I see at times.

Why he might improve in 2014:

Considering the biceps tear and the high ankle sprain, I would not be at all surprised to see improved play from McDonald in 2014. I don't think it necessarily means we see some serious dominance, but if he is healthy this season, it would not be shocking to see improvement from last year. McDonald turns 30 just prior to Week 1, so age is not on his side, but he's in a sort of unique situation. He put some serious tread on his tires in 2011 and 2012, with over 1,000 and 1,100 snaps in each year, respectively. However, in 2013 we saw him come back down to just over 800 snaps. And prior to 2011, he served four seasons as a reserve (although he did have 700 snaps in such a role in 2008). Maybe we see a bit of a resurgence in 2014.

Why he might regress in 2014:

Although he does not have a huge total of career snaps, he's gotten a lot of work since moving into the starting lineup in 2011. The 49ers were able to cut back on his snaps in 2013, thanks to Tony Jerod-Eddie and Demarcus Dobbs, but we also saw the biceps and ankle injuries. He turns 30 at the start of the regular season, so it would not be surprising if he was on the downside of his career. And furthermore, even if his skills do not regress, the addition of Tank Carradine to the current contingent of reserves like means even fewer snaps for McDonald in 2014. That could prove to be a good thing as the 49ers begin their transition to the future.

Odds of making the roster:

For this year, the likeliest scenario in which McDonald is not on the 49ers roster would seem to be a trade. If the 49ers are comfortable with Tank Carradine's knee, and they continue to think Tony Jerod-Eddie and Demarcus Dobbs are capable rotational options, they could try and move McDonald. He won't be cut this year, although if he sticks around this season, we could see him released next offseason. I think McDonald is on the team for 2014, but I would be surprised if he was around in 2015. Not shocked, but I think he is playing somewhere else in 2015.

Tank Carradine is the guy the 49ers are hoping is the future on the line, and with Smith nearing the end of his career, and McDonald probably not too far behind, the 49ers will want to get Tank in the mix extensively, as soon as possible. If Tank shows he can handle it sooner rather than later, that potentially speeds up the transition. This year's preseason will be interesting for so many reasons, but seeing Tank Carradine in the mix is high on my list. I'd love to see a strong year from Ray McDonald, but I can't help but be a little excited about the future.