4 returning 49ers who could struggle to fit in Chip Kelly's offense

Yesterday, we took a look at five non-quarterbacks on the 49ers roster who best fit into Chip Kelly’s offense and should see their production increase in 2016. Today, we’re moving to the opposite end of the spectrum. The four players listed below could struggle to find a role in San Francisco’s new offensive scheme, and in some cases, could even be looking for work elsewhere come September when the 53-man rosters are set.

Trent Brown and Andrew Tiller

Perhaps better known as "not Erik Pears and Jordan Devey," Brown and Tiller finished 2015 as starting offensive lineman for the 49ers and even looked mostly competent in the process, which you would have trouble saying about the men they replaced.

As things currently stand, the only change the 49ers have made to their 2015 group of offensive lineman is a swap of Alex Boone for Zane Beadles at left guard. This means Brown and Tiller would pencil in as the frontrunners for right tackle and right guard, respectively. The concern, if both players do in fact wind up in the starting lineup when the 2016 season opener rolls around, is that neither player appears to be a good fit in Kelly’s zone-based ground attack.

Physically, neither Brown (6-foot–8, 355 pounds) nor Tiller (6-foot–4, 324 pounds) fit the profile of a Kelly offensive lineman. The lineman who were on the Eagles’ season-opening roster during each of his three seasons in Philadelphia, per Ourlads.com’s archived depth charts, averaged just shy of 307 pounds. Kelly’s zone-based scheme, combined with the up-tempo pace, puts a premium on athleticism for offensive lineman. And unsurprisingly for mountainous men like Brown and Tiller, both players rank among the worst athletes at their respective positions according to the data from MockDraftable.com.

All of this showed up on film at the end of last season as well. San Francisco used more power-based runs late in the year, which allowed Brown and Tiller to utilize their considerable strength to move defenders on down and drive blocks. But when the 49ers went to zone runs the lack of athleticism showed, and both players often struggled reaching defenders and moving in space.

There are concerns with every non-Joe Staley offensive lineman on San Francisco’s roster, but how well Brown and Tiller can adapt and fit in to Kelly’s zone-run game, and what the 49ers will do on the right side if they don’t, are at the top of the list.

Bruce Miller

The former seventh-round pick and converted defensive end has been a valuable piece of San Francisco’s ground attack over the past five seasons, but it’s difficult to imagine Miller sticking in Kelly’s offense.

According to data from Football Outsiders Almanac, Kelly’s Eagles used one-back personnel groupings on over 95 percent of offensive snaps in 2013 and 2014 (data not yet available for 2015). Kelly never kept a fullback on the roster in Philly, opting to keep an extra wideout or tight end instead, which makes a lot of sense considering how often three or more receivers shared the field.

While it’s unlikely the 49ers iteration of Kelly’s offense will match the Eagles version verbatim, introducing a fullback on any significant number of snaps would be a drastic departure from anything he’s shown going back to his Oregon days. That means that if Miller has any realistic hope of carving out a role with the 49ers in 2016 and beyond, it will have to be as a tight end.

There’s little doubt Miller would be able to handle the blocking facet of the job, but to project success for Miller as a receiver in this new role would be to exaggerate his skills as a pass catcher.

Miller has been a semi-frequent target (for a fullback) in San Francisco’s pass offense, picking up 76 receptions over his five seasons. Nearly all of those receptions, however, have come on short throws into the flat; Miller has just five career targets on passes traveling 15 yards or more in the air. Miller simply hasn’t shown anything to suggest he’d be able to find success running the deeper, vertical routes Kelly frequently asks his tight ends to run.

To pile on another hurdle Miller would have to overcome, there’s the issue of size. Miller, who stands 6-foot–1, is short compared to the average tight end employed by Kelly in Philadelphia (6-foot–3). Size is important to Kelly, particularly for pass targets in the middle of the field, because of the types of defenses his teams often face. Single-high man coverage is the dominant coverage type Kelly’s offenses see, which means receivers must be able to either separate from their man defenders or make contested catches over them. There’s little reason to think Miller would excel at either.

Judging from Kelly’s public comments, it appears Miller will receive every opportunity to prove he can stick in Kelly’s spread offense. But based on everything we know about Miller, it’s hard to envision a scenario in which that actually happens.

Quinton Patton

There are several reasons you could point to in justification of Patton’s continued employment in San Francisco for the 2016 season. After Torrey Smith, the depth chart is filled with unproven young receivers. Jerome Simpson is the team’s only other wideout with notable NFL experience, and he’s hardly secured of even a roster spot. Opportunity is ripe for the taking among this group, and it would be difficult to argue that Patton is in considerably worse position to seize it than of the 49ers’ other receivers.

Patton is entering the final year of his rookie contract, which means that with a 2016 cap hit of only $772,875, per OverTheCap.com, he’s also cheap. San Francisco has oodles of cap space and a young roster that’s multiple years away from contending in the NFC West, so hanging on to an underperforming wideout for one more season at less than $1 million to see if he can develop under a new coaching staff is hardly a debilitating move.

Here’s the question I’m having a tough time answering: What is Patton’s unique value proposition? Is there anything he brings to the table no other receiver on the roster can offer in Kelly’s scheme?

Patton lacks Smith’s speed to threaten the defense vertically on the outside. At 6-foot–0, 204 pounds, he doesn’t have the size to fill the "big slot" role in Kelly’s offense. Patton’s best fit is likely as a sort of "space player" — an underneath receiver who can do some damage after the catch on screens and shallow crossing routes. However, Bruce Ellington brings more athleticism and versatility to that role.

So while it would be a surprise if Patton didn’t finish out his rookie contract with the team that drafted him, it’s unlikely he will do anything on the field to prove the 49ers should hang on to him for any longer than that.