San Francisco 49ers

New 49ers o-line coach has plenty of work ahead

San Francisco 49ers' Joe Staley (74), Colin Kelly (75) and Zane Beadles during NFL football training camp Sunday, July 31, 2016, in Santa Clara, Calif.
San Francisco 49ers' Joe Staley (74), Colin Kelly (75) and Zane Beadles during NFL football training camp Sunday, July 31, 2016, in Santa Clara, Calif. AP

The 49ers will have their fourth offensive line coach in as many years this season when John Benton's hiring becomes official. He takes over a unit that improved from 2015 when it was one of the worst in the NFL, but one that still gave up 47 sacks last year (third most in the NFL), is paper-thin as far as depth and needs plenty of attention. On Benton's to-do list:

Tackle heir: Left tackle Joe Staley remains the team's top offensive lineman, but his play fell off a bit last season -- he missed games due to injury for the first time in six seasons -- and he will be 33 when the new season begins. When Staley was injured, the 49ers had to tap left guard Zane Beadles to fill in. When center Daniel Kilgore also got hurt, Beadles went to center and rookie John Theus played left tackle. Theus is a possibility as a swing tackle, but the 49ers at some point must think about finding Staley's heir. When the draft began last year, they had three players circled for the No. 7 pick, defensive tackle DeForest Buckner and a pair of offensive tackles, Ronnie Stanley and Laremy Tunsil. (Stanly was taken sixth by Baltimore; Tunsil fell to 13th after video emerged of him using a bong while wearing a gas mask). In the past, the team has believed that Top 10 picks are meant for big-ticket items like quarterback, pass rushers and left tackles. Does the new regime share that thought, and is there a left tackle in this year's draft worthy of the No. 2 pick?

Skilled center: In an interview with MMQB last month, quarterback Brian Hoyer, who played for Kyle Shanahan in Cleveland in 2014, said there were a few things Shanahan needed to make his offense hum. One was a veteran center, and it's notable that the Falcons signed long-time veteran Alex Mack in free agency last year. The 49ers have a good center in Kilgore, but he's never stayed healthy for a full season since becoming a starter in 2014. His backup, Marcus Martin, has not been very stout and also has been injury prone in even a backup role. Undrafted Alex Balducci seemed to show promise in his first year after converting from the defensive line. He was a favorite of the 49ers after playing for both Chip Kelly and former defensive line coach Jerry Azzinaro at Oregon. Will Benton be as interested in the experiment?

Thin at guard: Despite drafting four interior offensive linemen in the first four rounds since 2012, the 49ers have little depth at guard. Beadles and last year's first-round pick, Joshua Garnett, are the starters. But the top backup in 2016, Andrew Tiller, is not signed for 2016 and another backup last year, fifth-round pick Fahn Cooper, is no longer with the team. Cooper ended the season on the practice squad and his contract expired. He is now a free agent who is expected to sign with another team. The 49ers have more pressing needs at other positions, but they will need to address their depth, or lack thereof, at some point during their rebuilding process.

49ers offensive linemen signed for 2017

C Alex Balducci

G Zane Beadles

T Trent Brown

G Andrew Gardner

G Joshua Garnett

C Daniel Kilgore

C Marcus Martin

OL Norman Price

T Joe Staley

T John Theus

Matt Barrows: @mattbarrows, read more about the team at

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