SANTA CLARA, Calif. - While the San Francisco 49ers might see a dramatic shift in their coaching staff next season, the same could be said for the defensive line, particularly after releasing Ray McDonald this week.
Much like the team's secondary that played without four key pieces from last year's group for most of the season, 2015's defensive line could see significant turnover.
McDonald and Justin Smith have combined to make 119 starts since 2011. Smith, 35, remains noncommittal about returning next year, after indicating he didn't want to hang around if he wasn't playing at his typically high level. Smith has been receiving treatment for a back injury since midpoint of the regular season, while regularly missing the first two practices of each week.
In 2014, Smith is Pro Football Focus' sixth-best defensive end in a 3-4 scheme, according to their grading. McDonald was 11th after registering 23 quarterback pressures over his last seven games.
After getting eliminated from postseason contention last week in Seattle, look for the 49ers' final two games to be key evaluation period second-year linemen Tank Carradine and Quinton Dial, who are San Francisco's only draft picks along the defensive line who figure into the immediate future.
"It’s all about how strong you can finish at the end," Carradine said. "So for me, these next two games are going to be really important to have for the season. So I feel like I’ve been getting better each week, so these last two games I need to make sure they’ll be even better than these last couple games."
After making his NFL debut in Nov. 9's win over the New Orleans Saints, Carradine has seen his playing time increase in recent weeks as Smith's backup on the right side of the defensive line.
Sunday in Seattle, Carradine had sacks on back-to-back plays of Russell Wilson in the fourth quarter. The first was a coverage sack, with Wilson trying to extend the play. The second came on a screen play in which fellow defensive end Tony Jerod-Eddie covered up Marshawn Lynch, which allowed Carradine to make the play for the nine-yard loss.
"He’s definitely getting better," defensive coordinator Vic Fangio said. "Feel encouraged by Tank’s play and definitely the arrow’s up."
Carradine did not make a favorable impression with Fangio either physically or in the mental side of the game after being drafted in the second round (40th overall) in 2013. He joined San Francisco fresh of ACL surgery and was unable to take the field until his practice window was opened deep into the regular season. Carradine struggled learning his assignments and wasn't the physical force the 49ers thought they drafted out of Florida State.
In February, Carradine had an operation on his injured knee to remove scar tissue to improve flexibility.
"To me, you throw out last year," Fangio said. "Last year was a total nonexistent year for Tank when it comes to learning and getting better playing football. It was a zero year for him. So, this was his rookie year. And he was struggling early, but he slowly was getting better and better. Then he hit another plateau. Struggled a little at that plateau, and now he’s taken off from that plateau."
Over the last three weeks, Carradine has played 28, 15 and 19 snaps in the team's three losses backing up Smith. Sunday's sacks were the first his career, indicating he's learned far more while playing than watching film in meetings.
"Just like anything you do in life, the more you do it, the better you’re going to get at it," Smith said. "(Carradine) keeps getting reps and keeps getting reps and getting out there and plays better every reps he gets. You become more aware of what you’re trying to do, (what’s) going on around you, how the defense fits off you...I think all that stuff’s starting to click for him."
Dial, drafted in the fifth round of the same draft, has been a more steady presence in his reserve role. The Alabama alum has been forced to play nose tackle with Ian Williams (fractured leg) and Glenn Dorsey (torn biceps tendon) out for the year.
Dial has started San Francisco's last five games and is another player earmarked for an increased role in 2015. Like Carradine, the start of his career was derailed by an injury. He had toe surgery after his final collegiate season while his rehab bled into his rookie year. He played in just 19 snaps in 2013.
"Quinton’s another good story through this storm that we’ve had. He’s had to go in and play nose," Fangio said. "Really wasn’t being trained to play nose very much in training camp, but because of the injuries there, we had to start doing that. He has stepped up like a man and played well in there for us."
With McDonald no longer with the team, head coach Jim Harbaugh said he expects Jerod-Eddie to start at left defensive end Saturday against the San Diego Chargers. The former undrafted rookie out of Texas Tech has played 35 percent of the snaps this season, backing up both Smith and McDonald.
With the team down a defensive lineman, Harbaugh said he expects nose tackle Mike Purcell to be elevated from the practice squad for Saturday's game. Purcell has been on the practice squad since the end of training camp after playing in 112 preseason snaps, where he performed well against the run and made seven defensive stops, according to Pro Football Focus.