Breaking Down The 49ers roster: Defensive Line

After examining the potential changes to the San Francisco 49ers' offense, it is now time to break down the situation on the defence heading into the off-season.

We start up front with the big guys on the defensive line.

San Francisco's defensive line performed admirably in 2013 despite suffering a major blow in week two of the regular season, when starting nose tackle Ian Williams was lost for the year with a broken ankle.

Williams was expected to be a key player for the 49ers this past season, but the defence adapted magnificently in his absence, with the performance of Glenn Dorsey proving key.

Dorsey, acquired on a two-year-deal following five seasons with the Kansas City Chiefs, performed beyond expectations, ending the regular season with 41 tackles and two sacks and negating the impact of Williams' injury.

Defensive ends Ray McDonald and Justin Smith both enjoyed strong campaigns, with veteran Smith once again proving adept at both generating a pass rush and creating holes for others to get to the quarterback.

Tony Jerod-Eddie and Demarcus Dobbs were used in rotation, the former proving to be somewhat of a revelation with his largely excellent performances.

All of the players mentioned are contracted for the 2014 season, although Dobbs can be signed as a restricted free agent for a tender of $495,000.

The form of the likes of Dorsey and Jerod-Eddie gives the 49ers depth on the defensive line, which is set to be boosted further by 2013 draft picks Cornellius (Tank) Carradine and Quinton Dial.

Injury disrupted the pair's respective rookie years, Dial playing in just three games, while Carradine missed the entire season as a result of the torn knee ligament he suffered in his final year at Florida State.

Both players are expected to return in 2014, however, of the two defensive ends it is Carradine who is tipped to add another dimension to the 49ers' defense.

Carradine was extremely impressive in his two years with the Gators, totalling 71 tackles and 16.5 sacks.

The 49ers hope that second-round pick Carradine's potential can be realised in the pro game but, although San Francisco have a wide number of options on the defensive line, the age of the group could soon be an issue.

It is unlikely that San Francisco chooses to select a defensive lineman early in the draft, yet with Smith now 34 and Ray McDonald approaching his thirties, it is a possibility that cannot be ruled out.

Notre Dame's Louis Nix III, Minnesota's Ra'Shede Hagemen and Florida State's Timmy Jernigan are all projected to go in the first round and have all been tipped as potential 49ers selections with a view to taking a starting role when the likes of Smith and McDonald move on.

Still, the 49ers are in the business of winning now and, with other issues to solve in the draft, I believe that San Francisco will put their faith in a supremely talented group of linemen.