Offensive linemen have long been the unheralded cogs that really make the machine run. Us fantasy footballers tend to prefer to deal with the glitz and glamour of the skill position players, but knowing how the big boys up front stack up could mean a world of difference for our points scorers. Let’s take a look at sixteen units by grouping them into four main categories:

Note: Most of my grades and metrics are coming from Pro Football Focus‘s Premium Stats

The Elite:

The cream of the crop: these are the best offensive lines in the NFL.

Dallas Cowboys

The Cowboys offensive line was dominant both in the run and the pass game in 2014 and only got better over the offseason by adding first-round caliber talent La’el Collins and third rounder Chaz Green to an already stacked group of three first rounders (Zack Martin, Tyron Smith, and Travis Frederick.) Collins will battle LG Ronald Leary for a starting spot and Green was brought in to help replace the departed Jeremy Parnell at swing tackle. The Cowboys are stacked with top-level talent and depth, making them one of the best units suited to adapt to injuries. The talent will obviously make whoever is running the ball a sought-after commodity. At this point it looks like that guy will be unproven third year man Joseph Randle, who, in my opinion, is worth a fourth round pick. The line is that good.

Baltimore Ravens

The Ravens were a top-three run blocking unit in 2014, and will bring back their entire starting five for the first time in franchise history. They also have quite possibly the best lineman in the league in guard Marshall Yanda (#1 rated lineman by PFF in 2014). Continuity and talent are the two most important attributes of an offensive line, and the Ravens have both. Losing zone-blocking guru Gary Kubiak to Denver hurts, but they appear to be keeping his scheme in place, so it’s not much to worry about. Just like with Dallas, whoever is running the ball for the Ravens this year is going to be a valuable commodity. Right now, that is Justin Forsett.

Green Bay Packers

It seems that Green Bay has assembled an elite offensive line in the opposite way that Dallas has. Out of their five starters, only one was a high draft pick (RT Bryan Bulaga). The rest are late round picks that turned into studs, like Packers players tend to do. Josh Sitton is a top five lineman in the league, and although LT David Bakhtiari is the unit’s weak link, he is still an average player. Center Corey Linsley had to be the team’s biggest surprise last year. He stepped in and excelled as a fifth-round rookie.

Same as the two units discussed above, the Packers return all five of their starters from the end of last year. You’re probably targeting all Green Bay skill position players regardless of how good their line is, but the difference in the Packers offensive line compared to the Colts may be a tiebreaker for the Andrew Luck/Aaron Rodgers top quarterback decision. The Packers were PFF’s top pass-blocking unit by far in 2014.

Cincinnati Bengals

Anchored by stud LT Andrew Whitworth (PFF’s second-highest rated tackle), the Bengals ranked in the top seven in both run and pass blocking last year. They return all starters in 2015, and also added tackles with their top two picks in April’s draft. Russell Bodine is somewhat of a weak spot at the center position, but he should improve in his second year. This line has talent, continuity, and depth. Draft Cincinnati skill position players with confidence that the team will have time to throw and space to run.

The Turnstiles:

Buyer beware: these project to be the worst offensive lines in 2015.

Miami Dolphins

It pains me to put the Dolphins on this list, because I love the talent of their skill position players so much, but they sure do deserve it: Miami graded out as PFF’s worst offensive line in 2014. Part of that can be blamed on the injury to LT Branden Albert, who was their eighth best tackle before he went down. The team has done little-to-none to address these issues, opting instead to spend money on pass catchers and Ndamukong Suh. Getting Albert back at full strength would be a huge help, but, with an ACL and MCL tear mid last season, his health status remains to be seen. If the Dolphins could manage to sign veteran guard Evan Mathis, that would also be a huge boost, but that looks unlikely at this point. Draft Dolphins with caution, but also realize that RB Lamar Miller averaged a terrific 5.1 yards per carry last year behind this line that surely can’t get any worse. I still see him as a solid third round pick.

St. Louis Rams

Tre Mason averaged 4.3 yards per carry as a rookie last year behind one of the worst lines in the NFL against some of the top defenses, so naturally the Rams spent a top ten pick to replace him instead of giving him help. The left side of this line has potential in #2 overall pick Greg Robinson and LG Roger Saffold, but the right side is a complete unknown. They’ll start two rookies: third rounder Jamon Brown at RG and second rounder Rob Havenstein at RT. Havenstein is a mauler in the run game but lacks the athleticism to be a great pass protector right off the bat. It’s tough to trust any Rams skill position players (yes, even Todd Gurley), and even tougher when you look at this line.

Carolina Panthers

The Panthers have still not reached step one in the Terrible Offensive Line Recovery Plan: “Admitting You Have A Problem”. The tackle position was what most considered to be the #1 glaring need for the team heading into 2015, and they did nothing to address it. They were ranked only above Miami and Tampa Bay in pass blocking last year, and throwing Michael Oher out there at left tackle will probably not help that much. It’d be nice to see a bounceback year from a healthy Cam Newton, but this offensive line may be the one thing standing in his way.

Tampa Bay Buccaneers

The Bucs were the worst pass blocking unit in the league in 2014, but unlike the Panthers, they’ve attempted to do something about it by drafting LT Donovan Smith and RG Ali Marpet in the second round. Both of those players will be given a trial by fire this season, as they’ll both be in the starting lineup on opening day. RT Demar Dotson sprained his MCL in the preseason and will be out six weeks, but the team did sign ex-Colt Gosder Cherilus to replace him. Maybe the line improves a bit from last year, but I can’t see how two rookies and a cast-off blocking for a rookie QB is going to go well.

Poised to Improve:

These offensive lines have made moves that could potentially improve their play from a year ago.

San Diego Chargers

At one point in 2014, the Chargers were down to their fifth center. That should tell you all you need to know about how this line performed (Second-worst in the league according to PFF). To provide some protection for newly re-signed Philip Rivers and some running lanes for first round pick Melvin Gordon, San Diego signed solid performers LG Orlando Franklin and RT Joe Barksdale. They also re-signed LT King Dunlap, who has been steadily improving and really coming into his own at the position. The moves should allow RT D.J. Fluker to kick inside to RG. With a finally healthy center, the Chargers are solid along the entire line and have the most improved unit on paper.

New Orleans Saints

The Saints traded for Pro Bowl center Max Unger, which should provide an immediate boost to the line. They also drafted tackle Andrus Peat in the first round, and although he has struggled in camp and probably won’t start, he will provide depth at the very least. The departure of Ben Grubbs should not hurt them much. New Orleans is clearly making a commitment to improving a unit that was already decent last year.

Arizona Cardinals

The Cardinals ranked near the bottom in both run and pass block grades last year, but the addition of second ranked run blocker Mike Iupati should improve the former dramatically. Arizona is also counting on improvement from #7 overall pick Jonathan Cooper at the other guard position. With LT Jared Veldheer anchoring the line and solid experience from all the backups, the Cardinals’ blocking should surely be better in 2015.

Cleveland Browns

The Browns had a top five unit in the league last season until Pro Bowl center Alex Mack went down for the year. After that, their performance fell off a cliff, yet they still managed to grade out as a top pass blocking line and above-average run blocking one – just showing how good they can be at full strength. LT Joe Thomas is the best offensive lineman of this decade and is still playing at an elite level. LG Joel Bitonio was one of the top rookies last year and should get even better, and rookie first rounder Cameron Erving should battle to start at RG and back up Mack at center in case he goes down again. There’s not a lot to love about the Cleveland running backs, but whoever gets the carries should have plenty of room to work with. Isaiah Crowell has a high ceiling if he can take over that job.

Poised to Decline:

These teams have made moves that won’t help their offensive lines in 2015.

San Francisco 49ers

The poor 49ers. Losing Iupati in free agency already hurt, and losing RT Anthony Davis to retirement added salt to the wound. The left side of the line is still solid, with perennial Pro Bowler Joe Staley at LT and another solid performer in Alex Boone at LG, but they’re definitely going to take a step back from their top three run block rank in 2014. This line was built around three stud first round picks, and now two of them are gone. To look on the bright side, though, Iupati was a negatively graded pass blocker so replacing him could help out in that regard.

Denver Broncos

The Broncos line struggled a bit down the stretch last year, but overall was still an above-average unit. The offseason was not kind to them, however, as they lost guards Manny Ramirez (trade) and Orlando Franklin (free agency) and left tackle Ryan Clady (torn ACL). Clady had a down year last year but has the talent to bounce back in Kubiak’s system. Instead, a second round rookie will protect Peyton Manning’s blindside. Yikes. There is now little experience in the Denver starting five, and fantasy owners will have to hope that Kubiak and Manning can help them grow up fast.

Seattle Seahawks

Russell Wilson’s mobility and Marshawn Lynch’s talent have masked the Seahawks blocking woes, but make no mistake: they’re not a very good unit. Trade the best player from that group away (Max Unger), and you can’t expect it to get any better. They did very little to address the line in the offseason, so Russell is going to have to do even more scrambling.

Philadelphia Eagles

The Eagles will still be a good unit in 2015. They have two of the best tackles in the league (Lane Johnson and Jason Peters) and one of the best centers (Jason Kelce). The issue will be at the guard position, where they will try to replace stud Evan Mathis. The current starters are Matt Tobin and Allen Barbre, who are both below-average if not downright bad. I wouldn’t avoid Eagles players due to this change, but it’s something to keep an eye on. An injury to one of their three studs could start to derail the offense.

SmartCheatsheet has columns for 2014 run and pass block rankings and our own algorithm for 2015 blocking projections. Make sure to add these to your cheatsheets if you want to take offensive line strength into consideration when drafting or creating your rankings.