There's a strong correlation between offensive line play and team success. Was thinking about that last night while watching the Chargers and Kansas City. The Chargers had one of the league's worst offensive lines as recently as a couple of years ago, and Philip Rivers was getting beat up (and struggling). Now, he's an MVP candidate.

In fact, a lot of the league's playoff teams, like the Chargers now, have among the league's better offensive lines. The run down:

PLAYOFF TEAMS (OFFICIAL)

Rams: Last week the Rams started the same five linemen that they'd started in Week 1: Andrew Whitworth, Roger Saffold, Johns Sullivan, Austin Blythe and Rob Havenstein. Small wonder that offense is performing at a high level nearly every week (Bears game excepted). Health, consistency, money (Whitworth), patience (Saffold), successful reclamation project (Sullivan).

Saints: The Saints have also been fairly healthy on the offensive line. Terron Armstead has missed some time due to injury, but he could return this week. They've gotten serviceable play from Jermon Bushrod filling in, and their other starters -- Andrus Peat, Max Unger, Larry Warford, Ryan Ramczyk -- help comprise one of the league's very best lines.

Chargers: The Chargers have a pair of reclamation projects who have worked out very nicely: Russell Okung and Mike Pouncey. With those veterans they've been set at the two most important spots on the line. Their draft picks haven't worked out as well (uh, Forrest Lamp?). But it's a really good line, and it held up pretty well last night.

Kansas City: In Eric Fisher, Cameron Erving, Mitch Morse and Mitchell Schwartz, Kansas City has had four quality players. They lost guard Laurent Duvernay-Tardif to injury, and it's a downgrade to fill-in Andrew Wylie. But that's the only negative.

PLAYOFF TEAMS (PROBABLE)

Patriots: New England let Nate Solder walk in the offseason, and he's been a disappointment with the Giants. Their rookie Isaiah Wynn got hurt early on, but their trade with San Francisco for Trent Brown -- a deal I never understood from the beginning for the 49ers, why would they do that? -- has worked out great. David Andrews, Shaq Mason and Marcus Cannon have also been solid. Teams like the 49ers and Browns (Josh Gordon) helping out the Patriots with stupid gift trades are part of why New England is always among the league's top teams.

Cowboys: Obviously Dallas has missed Travis Frederick, and second-rounder Connor Williams was a liability before getting hurt. But they've persevered with the good players still available. No longer the league's best line, but still a top-10 group.

Bears: The Bears have had more bad than good linemen in recent years; basically Kyle Long and a whole lot of disappointments via the draft and free agency. But the Charles Leno-Cody Whitehair-Bobby Massie trio has been at least decent, and given Mitchell Trubisky enough protection that he's having a solid year.

Seahawks: One of the stories of the season has been how the Seahawks turned around what had been one of the league's very worst lines in recent years; they now lead the league in rushing. Firing offensive line coach Tom Cable was a significant piece in the turnaround; once a respected guru, his methods were apparently antiquated in today's NFL. Seattle doesn't have elite personnel, but some reclamation projects (Duane Brown) and draft picks (Justin Britt) have panned out.

Texans: Houston's a bit of an anomaly, with suspect tackles (Julie'n Davenport, Kendall Lamm) causing protection issues at times for Deshaun Watson. But the interior is solid, which has enabled the team to emphasize the run.

PLAYOFF TEAMS (POSSIBLE)

Steelers:Offense really hasn't been why Pittsburgh has dropped three straight and could actually miss the playoffs (with tough games against playoff teams the next two weeks). It's still a top-10 line.

Ravens: Baltimore has shed some line talent in recent free agencies, and that's factored into why it's their defense carrying them to playoff contention. Look for them to focus on the line in the offseason.

Vikings: Minnesota's season-long inability to run the ball or protect Kirk Cousins is why this team is fighting for its playoff lives and will probably make a quick exit even if it gets in.

Colts: There's been nothing wrong with the Colts line, especially rookies Quenton Nelson and Braden Smith, rookie first- and second-rounders who've started all season. An above-average line that should only be better next year.

Titans:Tennessee just lost right tackle Jack Conklin, and that's a crushing blow, as he's one of the line's two best players.

Eagles: Nothing wrong with Philadelphia's line. It's the defense that's let this team down, with injuries a huge factor. (Offensive injuries, at running back and now to Carson Wentz, have also been significant.)