Drilling in: 49ers unit by unit analysis

Veteran tackle Joe Staley is back to lead the 49ers offensive line.Kelley L Cox-USA TODAY Sports

A detailed breakdown of the lineup

By Dave Del Grande

QUARTERBACKS: Starter -- Jimmy Garoppolo. Backups -- C.J. Beathard, Nick Mullens.

Getting five games under Garoppolo's belt last season was a godsend in that it lessens the amount he needs to absorb this summer. On one hand, the 49ers would love to see Garoppolo have all of Kyle Shanahan's weapons at his disposal in Week 1. That said, he did just fine with a shrunken-down playbook last December. Beathard demonstrated last season he's a fully capable backup.

RUNNING BACKS: Starters -- Jerick McKinnon, FB Kyle Juszczyk. Backups -- Matt Breida, Joe Williams, Raheem Mostert, Jeremy McNichols.

Never more than a part-time starter in Minnesota, McKinnon has a chance to be the breakthrough back of the league this season. He had 51 catches last season and gives the club a serious outside threat after endless plunges between the tackles by Carlos Hyde. That said, Hyde, who had totaled 50 catches in three seasons before the coaching change, amped up to 59 last season. Now imagine McKinnon doubling his previous output. The question is: How much can a 5-foot-9 back to counted upon? He has no proven backup, although 2017 fourth-round pick Williams might be an opportunity away from changing that.

TIGHT ENDS: Starter -- George Kittle. Backups -- Garrett Celek, Cole Hikutini, Cole Wick.

Shanahan can be old-fashioned at times with a fullback and multiple tight ends, but it works. Kittle (43 catches, two touchdowns) and Celek (21 catches, team-high four touchdowns) combined for 64 receptions last season, just five fewer than Rob Gronkowski. Hikutini adds depth to a position that could be used as trade bait should a one-for-one swap be deemed necessary on the eve of the regular season.

WIDE RECEIVERS: Starters -- Pierre Garcon, Marquise Goodwin. Backups -- Trent Taylor, Aldrick Robinson, Kendrick Bourne, Dante Pettis, Max McCaffrey, Victor Bolden Jr., Aaron Burbridge.

After a month of having everybody staring at him, Garoppolo likely will find the focus this preseason on who's most regularly on the other end of his throws. The 49ers hope that will be Garcon, once a 113-catch, 1,346-yard receiver in his prime. He was lost halfway through last season with a neck injury, but appears to be back at full strength. Well, full strength for a 31-year-old who's taken more than his fair share of hits (604 catches) in his career. Goodwin and potentially Pettis on deep patterns and McKinnon in the flat surround Garcon with the type of decoys that should maximize his open space between the hashmarks. Depth is an issue, especially if Pettis, more of a kick returner than a pass-catcher in college, is slow to adjust.

OFFENSIVE LINEMEN: Starters -- LT Joe Staley, LG Laken Tomlinson, C Weston Richburg, RG Joshua Garnett, RT Mike McGlinchey. Backups -- C Mike Person, C/G Erik Magnuson, G Jonathan Cooper, G/T Garry Gilliam, T Darrell Williams, T Andrew Lauderdale, T Pace Murphy.

The 49ers feature their deepest group in years, highlighted by three new starters who have come from three different places: free agency (Richburg), draft (McGlinchey) and injury (Garnett). Longtime stalwart Staley was so excited about the new look (and Garoppolo), he has decided to stick around at age 33. The pressure will be on McGlinchey to perform from Day 1 as Trent Brown's replacement at right tackle.

DEFENSIVE LINEMEN: Starters -- LDE Arik Armstead, LDT Earl Mitchell, RDT DeForest Buckner, RDE Solomon Thomas. Backups -- DE Jeremiah Attaochu, DE Ronald Blair III, DE Cassius Marsh, DE Kentavius Street, DT D.J. Jones, DT Sheldon Day, DT Jullian Taylor.

The success of the defense in large part will be dependent upon how effective former first-round picks Buckner and Thomas are playing side-by-side. Each is as capable of doing damage in the interior as he is getting to the quarterback from the outside, so the potential of that highly talented tandem seems limitless. The other side of the line is far less promising, although the 49ers anticipated the problem that is Armstead and successfully pursued Attaochu in free agency.

LINEBACKERS: Starters -- WLB Malcolm Smith, MLB Reuben Foster, SLB Eli Harold. Backups -- OLB Dekoda Watson, OLB Pita Taumoepenu, OLB Korey Toomer, OLB Elijah Lee, OLB Mark Nzeocha, MLB Brock Coyle, MLB Fred Warner.

Perhaps expecting the worst from Foster's legal troubles, the 49ers did more reshaping at linebacker than any other position. Like Armstead playing in front of him, the onus is on Harold to live up to his collegiate press clippings or fear not being around for the regular-season opener. The 49ers have raided the Seahawks (Coyle), Chargers (Toomer) and Vikings (Lee) for worthy replacements should they find the need to jettison Harold. Of course, everything revolves around Foster, who begins the season on a two-week suspension. That said, the former Alabama star has proven skill on the outside, so he's another option out there should the club feel more comfortable with Coyle or even the rookie Warner in the middle.

DEFENSIVE BACKS: Starters -- LCB Richard Sherman, RCB Ahkello Witherspoon, FS Adrian Colbert, SS Jaquiski Tartt. Backups -- CB/S Jimmie Ward, CB K'Waun Williams, CB DJ Reed, CB Greg Mabin, CB Tarvarus McFadden, CB CJ Goodwin, CB Antone Exum, FS Tarvarius Moore, FS Don Jones, SS Tyvis Powell, SS Chanceller James, SS Marcell Harris.

The 49ers could find themselves playing a game of musical chairs in a secondary where quantity surely surpasses quality. A healthy Sherman could change that, effectively allowing three defenders to focus on one side of the field while he shuts down the other. That might be what it takes to make Witherspoon successful in just his second season. Ward is the Andre Iguodala of the team -- way too talented to be listed as a backup, but someone currently awaiting his assignment. He could find himself in Witherspoon's spot, in Colbert's position, or simply keeping his fragile body fresh for use in various five-back packages. Rookies Moore, Reed and Harris all enter situations where the door to playing time is wide open.

SPECIAL TEAMS: K Robbie Gould, P Bradley Pinion, P Jeff Locke, LS Kyle Nelson, KOR/PR Dante Pettis, KOR Matt Breida, PR Trent Taylor.

You know you think you're pretty good when two of your key acquisitions in the offseason are a punter to compete with a guy who's been more than adequate and a kickoff returner. The 49ers wouldn't dare import competition for Gould, arguably their Most Valuable Player runner-up last season. His only concern: At age 36, he might not be able to keep up with all the opportunities Garoppolo provides. Pettis could quickly become a fan favorite at a position where the 49ers have been traditionally lackluster.